Series Continuity Error

""... and yet I also become annoyed whenever the great Homer nods off.""

- Horace, "Ars Poetica"

Certain facts or events are presented in a series that contradict earlier episodes. Bizarrely, this is sometimes done intentionally, or incidentally. Can lead to a Continuity Snarl or Continuity Drift.

A common feature of Long Runners.

Anime & Manga

 * In Tengen Toppa Gurren Lagann, Kittan is shocked by the notion of Kamina's hijacking of a Ganmen, claiming it's impossible. Parallel Works 9 shows Kittan actually stealing it. The problem? It's set before he meets Kamina, back when the Black Siblings were independent from Dai-Gurren. Note that the majority of Parallel Works videos (though not necessarily this one) are set in parallel universes.
 * In the second chapter of Ice Revolution, The Rival has clearly seen Tomboy Masaki in her girl's uniform yet in the next chapter she continues to view Masaki as a boy.
 * In Dragon Ball GT, in the second season, Trunks is able to detect No. 17's Ki, and is even able to compare it with that of No. 18... despite the fact that a major plot point in the background of the two androids when they were first encountered back in Dragonball Z was that they didn't radiate Ki at all!
 * The Artifact of Doom in the form of an eight-legged castle in the Nirvana arc of Fairy Tail could only be destroyed if the crystals at the root of each of its legs were destroyed simultaneously. The protagonists just barely manage to scrape together enough people with the strength left to fight so that they can post someone at all six crystals.
 * Lampshaded in Pretty Sammy TV Series when Romio appears as the third candidate who was flung into a Trap Door in the beginning. Rumiya pulls out the first episode and points out they look nothing alike.
 * Don't try to put Rave Master on a timeline. You just can't. Though, if you were to try, there'd really only be one little flaw in it -- Haru claiming that he's been fighting to save the world for two years when he's only been the Rave Master for a little over one.
 * Fist of the North Star has quite a number of continuity snarls as the series went on. For example, when Kenshiro's adoptive brothers were first introduced, Kenshiro initially mentions that none of them are actually blood-related. Later it turns out that the eldest two, Raoh and Toki, are blood-related after all and we are shown the ruins of their childhood home along with the graves of the birth parents. This can be handwaved by the fact that Kenshiro wasn't exactly sure himself. However, it later turns out that none of them were even born in Japan at all, but that the three of them were refuges from the Land of Asura and that Raoh and Toki's mother is buried in a swamp. If that wasn't enough confusion, then comes the prequel Fist of the Blue Sky, which shows that the baby Kenshiro was born in Japan.
 * In chapter 48 of Elfen Lied, Nana's sleeve, which was torn off in the previous chapter, reappears.
 * Bleach has had a number, and a particular example is Aizen's claim that Kisuke Urahara . In the "Turn Back the Pendulum" chapters, on the other hand, As this comes in the middle of a speech boasting about how evil he is and how he has, there's no reason why he'd be lying, either. Some, however, shrug the error as  being the official reason for his exile, it gave Aizen a chance to

Comic Books

 * Matt Olsen of the W.I.T.C.H.  comic series is one of the worst examples of this. When he first appears, he's a student with a thing for guitars, has a grandfather who owns a pet store and is utterly shocked when his girlfriend, Will Vandom, reveals her secret identity as a Guardian. However, come the second chapter of the New Power storyline and it's revealed that he's actually from Kandrakar, knows magic and already KNEW Will and her friends were Guardians. And there's been nothing to try to fix the previously established backgrounds.
 * In one part of Watchmen Dr. Manhattan is totally unfamiliar with the expression "What's up?" and takes it literally when asked. In another part he asks Janey Slater, "What's up, Janey?" This is a guy who experiences all times as one, and is most probably too Spock-y to have meant the first instance as a joke.
 * While everything above is certainly true, Dr. Manhattan experiences all time simultaneously but is nevertheless a slave to sequence -- if he's not meant to know something before the time he comes to know it, he doesn't know it, despite the fact that he actually does know it due to his knowing the future. He never acts on his knowledge of the future, he just reacts to the present as though he never had that knowledge to begin with.
 * In one issue of Bone, Rocque Ja cuts off Kingdok's tongue, and it's explicitly stated he can't speak with his tongue missing. Then, in a later issue, Kingdok is able to speak without any explanation given.
 * In the Asterix comics, Obelix's birthday is celebrated in Obelix and Co., just Obelix's. But in Asterix and the Actress, it is revealed that Asterix and Obelix were born on the same day and they celebrate their birthdays together.
 * In Ultimate Fantastic Four, The Maker Reed shows to Falcon how he keeps his intellect always a few steps ahead of The Children by enlongating his brain, that shouldn't be possible or even necessary; to elaborate: in the first run of UFF Sue ran some tests on Reed and found out that his organism was completely mutated, he became a worm-like being with just a core, no organs other than that, and later Sue's mother remarked that Reed was getting smarter by the minute due his mutation; so in the spam of a thousand years Reed would be evolve his genius naturaly, and there would be no brain for him to enlongate.
 * In The Smurfs, the story The Finance Smurf introduces the money system and the Smurfs are revealed as not knowing what money is at all. This contradicts earlier stories, such as The Egg and the Smurfs where a Smurf makes a wish to become "rich" -- and ends with jewels and money as a result -- and in Smurf Stories where a Smurf creates a machine that can turn hazelnuts into gold coins and the Smurf tells Papa Smurf he'll use the coins to buy more hazelnuts.
 * Fables. This is done as a plot point. It used to be 'John of All Fables' but the 'author' made a typo so the universe created the Loveable Rogue Jack of All Fables. Jack meets John later on. Chaos ensues, which it usually does around Jack.
 * Transmetropolitan's resolution famously revolves around a picture taken by a minor character. Unfortunately, said minor character is given the camera long after the event she is supposed to have taken a picture of.
 * In a Teenage Mutant Ninja Turtles Mirage comic -- early in the "City at War" arc -- the Foot Soldiers are shown knowing the location of the Turtles' lair since they had apparently "raided it before". This event happened in the first theatrical movie -- never in the Mirage comics.
 * Doctor Strange states near the climax of Avengers Disassembled that there was no such thing as chaos magic. The good doctor has used chaos magic before. Using the terms from the old Marvel Super Heroes RPG, his Arch Enemy has been a chaos magic master for going on forty years now. Kind of impressive for magic which doesn't exist, right?
 * In an issue of Alpha Flight, speedster Northstar is suffering from a disease since Pestilence, that storyarc's bad guy, kissed him. Problem is, said kiss won't happen until the following issue. (Northstar's illness was originally intended to be AIDS, because, you know all gays have AIDS, and you can get it from a kiss on the forehead.).

Comic Strips

 * Peanuts
 * A comic strip from 1959 has Snoopy say that he doesn't have any siblings, yet they appear later in the strip's run (and were mentioned in this 1970 strip). To make matters worse, when he does first meet his siblings in the strip he claims they all speak different languages, which is also later shown to be false. He also started calling Charlie Brown the "round-headed kid" around the late 1960's, even though he called him by his name earlier, although that could be more of Characterization Marches On.
 * Even though Violet's birthday is apparently June 17th, according to the June 17, 1962 strip, a couple of the 1950's strips hinted her birthday is January 28th: In the February 22, 1951 strip, she said her birthday was last month, and in the January 29, 1955 strip, Charlie Brown said her birthday was yesterday.

Films -- Animation

 * At the end of the first Aladdin film, the Genie loses his cuffs as a result of him being freed by the title character using his third wish. However, in the sequel, he for some reason started to wear cuffs again. The TV series finally Lampshaded this in one episode by having Genie say, "The only thing I'm a slave to is to fashion!", implying that he wears his cuffs because they look good on him.
 * The Disney Direct to Video film The Lion King 1½ (which is essentially a recap of the first film's events, but from Timon and Pumbaa's point of view) actually contradicts the events of the first Lion King film on so many levels. It also contradicts the animated television series that followed Timon and Pumba. Though, given whose points of view it's told from...
 * At the end of Disney's Atlantis the Lost Empire, Kida actually gains more tattoos on her face, but in the sequel, all of her tattoos save her first one are inexplicably gone!
 * The Hunchback of Notre Dame
 * Esmeralda mysteriously started to wear her Gypsy outfit again (although with a pair of shoes, she was barefoot in the first film) in The Hunchback of Notre Dame II, despite the fact that said outfit as well as all but one of her other dresses (including the one she poledanced in at the Feast of Fools) were implied to have been destroyed by Frollo at the end of the film so he can have her executed properly, which leaves her with a white dress in which Esmeralda would have been burned alive in.
 * Also in the same film, her new husband Phoebus mysteriously gains his armor back despite losing it near the end of the first film, much like his wife Esmeralda ending up wearing the white dress.
 * Even more jarring, the little girl who hugged Quasimodo at the end of the first movie is present at the start of the second movie, unaged at all even though enough time has passed for Esmerelda and Phoebus to have a young son.
 * Winnie the Pooh: Piglet's Big Movie recounts how Kanga and Roo first came to the 100 Acre Woods. Tigger takes part in the event, even though Pooh and the others first met Tigger in Winnie the Pooh & the Blustery Day, in which they already know Kanga and Roo.

Films -- Live-Action

 * In The Princess Diaries, Mia's birthday is stated to be after Genovian Independence Day. In the sequel, her birthday is before Genovian Independence Day.
 * Two big examples from the Star Wars films:
 * First is the conflicting ages of the Republic given by Obi-Wan and Palpatine. In A New Hope, Obi-Wan establishes that the Jedi have been protecting the Republic for "a thousand generations" (anywhere from 15,000 to 30,000 years depending on how you count a "generation"). In Attack of the Clones, Palpatine says that he will not let "this Republic which has stood for a thousand years" fall. Even factoring in that Obi-Wan may have been exaggerating (which, according to the Expanded Universe, he wasn't) that's a pretty big difference in ages.
 * Another example is Leia remembering her mother as established in Return of the Jedi, only for Padme to die within minutes of Luke and Leia's birth in Revenge of the Sith. There have been attempts to explain this, such as the novelization implying Leia was "trying to take in every detail" or some fans' speculating Leia was referring to her foster mother but even Leland Chee, the man responsible for sorting the massive convoluted Star Wars continuity, says that he's stumped.
 * Asajj Ventress is changed from a true Rattatak to a Dathomirian taken to Rattatak and being raised there until her descent to the Dark Side after her mentor is killed by soldiers.
 * Darth Maul surviving Obi-Wan Kenobi's attack at the end of The Phantom Menace and becoming half-robotic.
 * The Halloween films:
 * At the end of the first movie, Michael is shot by Loomis six times, then falls off a covered balcony at the back of the house; this scene is shown again at the start of the sequel -- and Loomis shoots Michael seven times (despite only having a six-chamber revolver), sending him flying off an uncovered balcony at the front of the house. Made all the worse when Loomis goes around shouting "I shot him six times!" in the first few minutes of the film.
 * Also in II, Loomis says that Michael is 21 years old. Both end credits of the first film and II lists unmasked Michael's age as 23.
 * In the original Halloween, the Myers house is a modest two-story home. By the time we get to Halloween 5, it's a huge, Gothic-style mansion.
 * In Star Trek II the Wrath of Khan, Khan recognizes Chekov despite the latter being introduced in the second season of Star Trek the Original Series. The episode with Khan was part of the first season. One theory is that, since Chekov never got a formal introduction episode, he could've been in the lower decks since Day One and been promoted to bridge officer after Khan's banishment. It wouldn't even be the first time someone's shown up on screen out of nowhere and been treated like they were on the show the whole time. Walter Koenig likes to joke that offscreen they met when Chekov kept Khan waiting at a restroom, then left him with no toilet paper, hence Khan remembering him.
 * In Star Trek III: The Search For Spock, Kirk flashes McCoy the Vulcan hand salute in a throw-away joke ("How many fingers am I holding up?"). Unfortunately, it has been established as recently as the end of the previous film that Kirk cannot manage the Vulcan hand salute (as seen in the infamous sequence in Wrath of Khan where Spock is slowly dying in the radioactive containment until).

Literature
"He was not at all easy about the wounds which Don Belianis gave and took, because it seemed to him that, great as were the surgeons who had cured him, he must have had his face and body covered all over with seams and scars."
 * Harry Potter
 * In Harry Potter, Lupin says that he was unlikely to be admitted to Hogwarts, but then Dumbledore became Headmaster. This sets Dumbledore's promotion about 1970 or so. But Harry Potter has Dumbledore become Headmaster around 1955, before Lupin was even born. This is because Writers Cannot Do Math. Rowling herself confirmed it.
 * Also, Harry fails to notice the Thestrals pulling the carriages at the end of Goblet of Fire only to do so the next book. J.K. Rowling herself says that this is because she didn't want to add the Thestrals at the end of a book, stuffing it. Her in-universe explanation is that takes some time to "process" a death and come to terms with it; only after then can you see Thestrals. It is also worth noting that he didn't see his parents die at all, not even his mother. He was lying in the crib and only saw green light fill the room. Both J.K. Rowling herself and the seventh book confirm this. This explains why he was not able to see the Thestrals from the beginning of the first book. Link.
 * It still creates a major plot hole for the films. In the novel, he passes out before he can see Quirrel burn up, but in the movie, he's a first-hand witness to the whole process in all its nightmare-inducing detail. Maybe Quirrel's death wasn't sufficient since he only had a "half-life"?
 * It also creates a plot hole for the movies in that, though the explanation that the death needs to be "processed" might explain this.
 * In the first book, Voldemort tells Harry that his father "put up a courageous fight" before he died, and had no reason to be lying to Harry at this point. Seven books on, James Potter is killed in flashback without raising so much as a finger against Voldemort, though James did try to hold him off, but was killed quickly, having forgotten his wand. Perhaps, given that he was going against the Evil Overlord unarmed, instead of begging for mercy, Voldermort would have considered fighting him at all to be brave. He didn't say he was a tough fighter, just a brave one.
 * In Harry Potter, Harry and Voldemort duel, and because their wands are made from the same source (Fawkes the Phoenix), it creates a Phlebotinum effect that causes the spells Voldemort cast to pop back out of his wand in reverse order. An early edition of the book suggested that Harry's Mother was killed before his Father, which contradicted every description of their final moments. Rowling later admitted the mistake. Later versions of the book, and the movie, fix this.
 * The Death Eater called Rookwood has the first name Augustus in the first book he's referred to in, Goblet of Fire. It changes to Algernon in Order of the Phoenix, but reverts afterwards.
 * Marcus Flint was said to be a sixth year student in Philosopher's Stone but was still at Hogwarts in Prisoner of Azkaban. Rowling has suggested Flint had to repeat a year.
 * In The Bartimaeus Trilogy, it was established that certain commoner children are whisked from their homes to be apprenticed to a magician, and forget their family and even their name. Yet Arthur Underwood has a desk that's "a family heirloom", and a photograph of his grandmother in his study. Also, in The Amulet of Samarkand, Arthur says Bartimaeus would have to be a djinni of "at least the thirteenth level", yet later he is described as fourth-level. And later as sixth level. On the other hand, Arthur's magical abilities are held in contempt by pretty much everyone (including his twelve-year-old apprentice), so that's not quite as bad (and depending on where the information on Bartimaeus' levels came from, spirits do enjoy inflating their own reputations and deflating their rivals').
 * Tom Holt's Portable Door series. The first book stated that using the Door for a journey of more than an hour was almost impossible, and using it for any real length of time was exhausting. By The Better Mousetrap, Frank Carpenter is living his entire life about two decades in his past thanks to the Door, without really experiencing any negative effects whatsoever.
 * Dr. John Watson of Sherlock Holmes seems to get caught in these rather often.
 * Watson served as an Assistant Surgeon of the Army Medical Department (attached to the 66th Foot) in Afghanistan, but was discharged following an injury received in the line of duty during the Battle of Maiwand. In a Series Continuity Error, his wound shifted from shoulder to leg. This is referenced in the Guy Ritchie film, where Watson limps throughout the film but is also wounded in his shoulder by shrapnel near the end, and in Sherlock, where he was shot in the shoulder, but has psychosomatic pain in his leg.
 * Doyle's stories -- which sometimes assigned Watson a wife, sometimes didn't, and sometimes referred to Watson as a widower, never in chronology -- hopelessly confused the issue of just how many wives Watson had. W.S. Baring-Gould, author of a well-researched "biography" of Holmes, decided Watson had three wives. Others have suggested numbers up to six.
 * Both "The Final Problem" and its prequel, The Valley of Fear, involve Watson hearing about Moriarty for the first time. The latter apparently makes Moriarty aware of Holmes' activities against him two years earlier than the former does.
 * To add insult to floating injury, Watson's first name is in question. It's stated as John H. Watson at least once, but in "The Man With the Twisted Lip" his wife calls him James.
 * Christopher Paolini, of Inheritance Cycle fame, gave Murtagh dark brown hair in Eragon, but his Adaptation Dye Job in the movie seems to have confused the author enough for Murtagh to have a different color by Brisingr
 * Earlier Andrew Vachss Burke books said that Badass martial artist Max the Silent was a Mongolian, but the first mention of his nationality in Terminal has him as Tibetan. It's even more messed up when the next time says he's Mongolian again. Supposedly the Tibetan thing is established in the first book, but as later books never spell it out clearly in full, you can see how this confusion arises.
 * Don Quixote: For a book that only has one continuation, there are various examples of those errors. Then again, Cervantes was mocking those fans who put too much attention to continuity... There are two types:
 * Lampshaded in-universe: Fan Dumb
 * Chapter I, part I: Alonso Quijano has some continuity questions about The tale of Don Belianis of Greece:

A lot of the continuity errors are explained retroactively in Thief of Time -- the History Monks have had to repatch history several times, and it tends to have some effect on the present as well. P Terry's said in interviews, "There are no continuity errors, only alternate pasts."
 * Played straight in the book:
 * Sancho's donkey disappearance.
 * The lad who helps them with the field and the marketplace.
 * Those hundred crowns that Sancho found in the valise in the Sierra Morena.
 * Sancho talks about using a sword at Part I Chapter XV and the Barber mentions Sancho has a sword in his hips at Part I Chapter XLVI, but at Part II Chapter XIV, Sancho denies ever having a sword.
 * The name of Sancho’s wife changes at the same page in Part I Chapter 7 (Juana Gutiérrez and Mari Gutiérrez), and the same at Part II Chapter V (Teresa Panza and Teresa Cascajo) and in Part II Chapter L, Teresa Panza).
 * Animorphs
 * In the first book, Visser Three snidely comments that it's an honor to meet Elfangor right before This directly contradicts the backstory concocted later on, wherein the two characters have extensive history, not even counting all of the timeline changes that take place.
 * Animorphs has quite a few of these in the first book or two, with one of the more obvious being Jake using Thought-speak on Tobias when Tobias is a cat and Jake is still unmorphed. Later books have them discuss the inability to use Thought-speak outside of morph.
 * The Dirk Pitt novels by Clive Cussler all take place in the same continuity, with past events often mentioned. At the end of Trojan Oddessy, Dirk marries congresswoman Loren Smith, his love interest for most of the series. In the preparations for the wedding, it states the Loren's parents flew out to attend. The plot of Vixen 03 revolves around the murder of Loren's father twenty years previously, and it was stated that he was already a widower when he died.
 * In The Chronicles of Narnia, Aslan tells people on various occasions that "no one is ever told what 'would have happened'". The wording is unequivocal. Then in The Magician's Nephew he tells someone "what would have happened". He even uses those very words. It may be writer error. On the other hand, he created Narnia, has used deception before, is "not a tame lion" (he doesn't usually follow any rules but his own), and the decision in question was one of the most important ones in Narnia's history.
 * In the Flashman series, Flashman has an uncle Bindley who works at an office responsible for assigning military commissions, and at a couple of points, Flashman is forced to seek his help getting a commission. Consistent in the books is that Bindley dislikes Flashman, but the reason for this depends on the book. In the original novel, Bindley is from the aristocratic side of the family and doesn't like Flashman because he's from the commoner side. Later books reverse this by having Bindley as the commoner and resenting Flashman, who looks down on him. It's possible that this is a deliberate use of Unreliable Narrator, since the novels are supposedly extracts from memoirs Flashman wrote as a very old man.
 * The Star Wars Expanded Universe seems to have these aplenty. Some biggies:
 * Dac or Mon Calamari? Retconned as Dac being the indigenous name for the planet.
 * The Marvels introduced us to "your father, Darth Vader, and Obi-Wan Kenobi". Also, Obi-Wan has black hair. The actual phrasing was "Obi-Wan, Darth Vader and the man who carried Anakin Skywalker's lightsaber", certainly implying Anakin and Vader were two different people. In one of the deftest RetCons in the Expanded Universe, an author was able to use a pre-existing Jedi ritual to justify the man carrying the saber as a third, distinct Jedi who had swapped sabers with Anakin at the time.
 * Chewie only having one son when Word of God says Wookiees have multiple births. And six breasts.
 * Children of the Red King: When Lysander's mother appears in book three, she's named Jessimine. In book five, she's named Hortense, which was the name of one of her daughters.
 * Happened towards the end of the Teenage Worrier books. Among other things, Hazel's name in the first book is Hazel Williams and she attends an exclusive school called St Mary's Academy; in the last, her name is Hazel Appleby and her school is St Cheyngangg's (with no mention of her changing schools).
 * In Mercedes Lackey's Dragon Jousters cycle, the only one of Kiron's sisters whose name is given is the one who was so severely beaten by soldiers in the backstory as to cause permanent brain damage. However, at one point in the first book, Kiron remembers her name as Deshara; at another point, her name seems to be Dershela. And in the fourth book,, her name is Iris.
 * Heralds of Valdemar
 * The chronology of the Tedrel Wars and Selenay's early reign is set in Exile's Honor and Exile's Valor. Skif's teacher in Take A Thief claims to have been crippled at the beginning of those wars, but according to him they started at least 15 years before the dates in the "Exile's" books.
 * The first two novels of the Mage Storms trilogy cover less than a year of time. Tremaine manages to age from around 30 years old at the beginning of "Storm Warning" to 45 years old in "Storm Rising". Another inconsistency in those novels is the official cult of the Eastern Empire, which goes from the "Forty Little Gods" to the "Hundred Little Gods".
 * The timeframe in which Selenay's first husband and father-in-law die changes continuously. When the series was first written, it was implied that the two died at roughly the same time with the notifications of their deaths crossing en route. In By The Sword, it was stated that learning about Thanel's attempted assassination of Selenay was a contributing factor to his father's decline and death. In Exile's Valor, Thanel's father dies about a year before Thanel himself does.
 * The Elemental Masters novel The Serpent's Shadow cannot make up its mind about the name of Maya's father. He is mentioned by name twice. The first time his name is Nigel, the second time his name is Roger.
 * And in Unnatural Issue, Susanna makes a charm bundle and uses it to create a doppleganger of herself so she can sneak off to practice magic. When she runs away from home she's specifically described as burning the bundle and scattering the ashes, as it could be used against her if it got into her evil father's hands. Yet towards the end of the novel it's said that the bundle could not be destroyed by mere burning as it was a magical object and Susanna still had it with her--conveniently, as the good guys could then use it in their plan to draw out dear old dad.
 * Happens many, many times with the Warrior Cats series : characters often change pelt colors and occasionally flip genders, sometimes they'll forget what certain characters know and don't know, time passage will be inaccurate, and some details about Clan life and the history of the Clans have gotten changed around. Seeing as there's over 40 books, graphic novels, and guidebooks, over 700 characters, and four people writing the series, it's only natural that things get mixed up once in a while.
 * Happens occasionally in The Dresden Files, usually minor instances, which author Jim Butcher tends to acknowledge on his website. In Proven Guilty, the narration describe's a family's minivan being crushed flat, with the next chapter mentioning the whole family piling into the same minivan. In Ghost Story, a gunman's weapon changes from a snubnosed revolver to a semiautomatic between chapters.
 * There's a few in the Discworld novels; apart from the characterisation of Death and the Patrician, there's things like the gates of the Assassins' Guild which in Pyramids never close because Death is always open for business (and also because they rusted years ago) but are firmly closed at the end of Men At Arms. The confusion in the early books about who trained the young Esme Weatherwax is eventually resolved when she explains she went round all the local witches and basically bullied them into teaching her.
 * In a clear case of the writer and editor falling asleep, in at least the original hardcover of A Song of Ice and Fire's A Feast for Crows, Princess Arianne discusses the implications . A scant three pages later, she is first informed about it happening.
 * In the Garrett P.I. series, Glen Cook once had his sleuth refer to his stable-keeping friend Playmate as "Sweetheart". Cook later justified this, having Garrett mention how he'd once made it a practice to call Playmate by an alias, to divert the attention of some thugs who might make trouble for his friends.
 * The Vampire Chronicles is riddled with continuity errors, some of which can be written off due to the fact that different books have different narrators. However, it's hard to understand how Lestat's eye-colour, even self-described, keeps shifting.
 * In "Queen of the Damned," Jesse Reeves sees spirits as a human but completely loses this ability when she becomes a vampire. It's made quite clear that vampires do not possess this ability. In the next book, Claudia's ghost appears to Lestat... well, it's a ghost of a vampire so maybe the rules are different. However, Merrick becomes a vampire and retains her ghost-seeing abilities, which nobody seems to think is that unusual.
 * The Elric Saga: Elric's mother died giving birth to him, according to Elric of Melniboné. However, in The Sailor on the Seas of Fate he reminisces about his parents in a way that suggests that his mother as well as his father was still alive at a time when he was old enough to remember her.
 * In the Spellsinger series, Mudge the otter has kids as of the sixth book. How many, and what their names and genders are, changes from #6 (daughter Prickett and two sons) to #7 (son Squill, daughter Neena), and again to #8 (Squill and Nocter, genders not stated). Granted, Mudge isn't the most organized of fellows, but you'd think he'd keep track of who his kids are.
 * The Jeeves and Wooster story "Bertie Changes His Mind" (reprinted in Carry On, Jeeves) revolved around the fact that Bertie was considering moving in with his sister and her family, although they never actually appeared. Later, in Thank You, Jeeves, Bertie is asked whether he has any sisters and replies in the negative.
 * The Riftwar Cycle: The later novels have quite a few continuity errors. For instance:
 * Eric von Darkmoor mentioning that he had never married when he got married in Wrath of a Demon King.
 * The Tsurani Emperor appointing a Warlord in Wrath of a Mad God, generations after the title was abolished and replaced with a similar position with no attached political authority in Servant of the Empire.
 * In the same book, mention of House Minwanabi, every member of which had committed ritual suicide at about the same time as the position of Warlord was abolished.
 * The story Jimmy the Hand taking place in Land's End, resulting in virtually all of the nobility of that small region dying, which makes the long-established recurring minor character Squire Locklear of Land's End's backstory nonsensical, especially since his first appearance in the timeline is only about a year later, nowhere near enough time for the new Baron, who had no siblings, to marry, produce an heir, and have that heir grow old enough to be sent as a squire to the Prince's court.
 * The Book of the Dead can't seem to decide what colour Constance's eyes are; at the beginning of the book, they're violet, at the end of the book, they're blue, and in the preview for the next book, they're "dark".

Live-Action TV

 * One of the most famous examples is The Golden Girls. At some point, they hired a new writing team who simply ignored previous continuity in favor of Rule of Funny. Some famous examples:
 * In one episode, Dorothy mentions that Rose is allergic to cats. However, in a flashback of how Rose and Blanche first meet, Rose mentions that she was thrown out of her apartment because her landlord didn't allow her to keep a cat she found, and was holding at the time. Although, this could be Handwaved with Rose's caring nature, she might put her personal pain aside to help an animal in need. Or that Rose developed the allergy after that incident.
 * The most famous is Dorothy's children. Dorothy and Stan were married for 38 years, and the show began two years after that. Considering Dorothy had a shotgun wedding, one of her children needs to be at 40 for this to make sense. Although both of her kids were played by multiple actors over the years, none of them appear to be over 30.
 * Dorothy is also stated to be a grandmother early on in the series, having a grandson named Robby. However, neither of Dorothy's children that make an appearance are shown to have children.
 * Depending on the Writer, Blanche can have between 4 and 6 children.
 * In the Wizards of Waverly Place episode "Art Teacher", Mr. Laritate is surprised that his phone gets text messages when a teacher "texted in her resignation." In a later episode, he apparently still doesn't know what a text message is.
 * Star Trek has a ridiculous number of examples. They include:
 * In their first appearance, the Ferengi were aggressive, militaristic imperialists. In later appearances, they are portrayed as craven, greedy people with few cultural arts outside peddling and trading. This was an Author's Saving Throw; they'd planned to make the Ferengi the new Big Bad Aliens of the franchise, and they didn't realize until the episode was already wrapped and aired that they'd utterly failed at it. So they cut their losses, rewrote the Ferengi (and changed their uniforms to something less silly), and brought back the Romulans.
 * The original series episode "Space Seed" was made during a time when a specific year wasn't yet assigned to the canon, so it references things in blocks of time... but misses the mark by a hundred years when Wrath of Khan came out. Whoops.
 * The Borg story has a sketchy chronology. Q set Picard's Enterprise thousands of light-years to find the Borg for the first time, and eighteen months later they came looking for Earth. Guinan identified the Borg in their introductory episode and it was later revealed that Guinan and her people migrated during Kirk's time. Voyager introduces Federation scientists (Seven of Nine's parents) studying the Borg long before Picard's first contact. It messed up what was inferred in the original episode, but it does make some sense that Guinan's people could have reported it to the Federation and it just didn't become common knowledge until the official first contact.
 * In the Borg's first appearance in "Q Who?" they're only interested in "consuming" technology, and ignore other lifeforms unless they see them as a threat. When they take Picard in "Best of Both Worlds", he's chosen to be a spokesman, not a drone. It's only after this that we're told assimilating other lifeforms is their standard MO, and always was.
 * The vanished outposts in the first season finale, "The Neutral Zone", were meant to be foreshadowing of the Borg (In "Q Who?", they encounter an identical pattern of destruction after Q displaces them), implying that the Borg were probing the edge of Federation space even before Q made formal introductions. This is never mentioned again, and Guinan would later claim that, thanks to Q's intervention, the Borg discovered humanity centuries sooner than they ought to have done.
 * Data's cat was repeatedly referred to as male since it was introduced, then suddenly became female in the last season and even had kittens. Some Fan Wank this as his owning several cats over the years and giving them all the same name, which would seem to be in character.
 * There were continual goofs in whether Lieutenant Commanders are referred to as "Lieutenant" or "Commander" formally. They could probably have gotten away with either regardless of real-world behaviors if they had just chosen one and stuck with it.
 * In the Star Trek Deep Space Nine episode "The Alternate", Sisko strongly implies that his father is dead. This contradicts later episodes where his father is very much alive and running a restaurant in New Orleans.
 * As pointed out by Phil Farrand in the Nitpicker's Guides, O'Brien is casually treated as an officer (and once referred to as a lieutenant) in Next Gen but is explicity and insistently a noncommissioned officer in Deep Space Nine.
 * In one episode of The Big Bang Theory, Sheldon admonishes Leonard for ending a sentence with a preposition. Anyone with even a cursory ability to recognise grammatical structures would remember that Sheldon has never been adverse to this. This may be because the writers didn't think anyone would notice when they came up with the gag, or because the writers didn't know anything about the "taboo" of ending sentences with prepositions until they wrote that gag and then promptly forgot about it afterwards.
 * Doctor Who
 * The show has two different origins for the Loch Ness monster -- an alien cyborg and a mutated overlord thrown back in time.
 * And three mutually exclusive explanations for Atlantis.
 * Also from Who is the notorious UNIT dating problem. In "Pyramids of Mars", Sarah Jane Smith is from 1980, and the last time she was there, the Brigadier was still heading UNIT ("Terror of the Zygons"). In "Mawdryn Undead", the Brigadier retired in 1976, taking up a position as mathematics teacher through 1983. Lampshaded in the series 4 episode "The Sontaran Stratagem", when the Doctor tells Donna he used to work for Unit in the 70s... or maybe the 80s...
 * In the revived Doctor Who, the Doctor continually insists that he is 900 years old, which by "The Impossible Astronaut" became 909. This despite the fact that in the original series, the sixth Doctor also claimed to be 900 years old, and the seventh said once that he was 953 in Time and the Rani. Given that the remainder of the seventh Doctor's life and all of the eighth Doctor's life is lived out after this point, the ninth and tenth Doctors must be far older than 900 years old. And to top it all off, he's used the nine hundred figure for his age, how many years he's been time traveling, how much "phone box" travel he's done (which would have to be from the first episode of the original series, when it got stuck like that, and not how long he's used the TARDIS) and how long he's been using "the Doctor" as a nom de plume, four discrete and mutually exclusive things. He may just like the number. Word of God states that he has no way of remembering his exact age, and even if he did, he might be in denial over the big 1-0-0-0. By "Closing Time", he finally pushes past the 1100 mark, however, it's clear from dialogue in "The Impossible Astronaut" that hundreds of years have passed since the previous episode "The God Complex".
 * "The War Machines" has the computer WOTAN actually say "Doctor Who is required". Even the most casual fans know that he isn't called that. The name is only ever used as a joke ("Who is he? Doctor who?")
 * In general, the show has even come up with an in-universe explanation which can act as a general retcon whenever needed; the Time War has just gone around screwing with the Time-Line! Whole events have literally been wiped out of existence (unless you're a time-traveler, because then you can remember them).
 * In the earliest episodes, they talked about the ship. TARDIS was only Susan's nickname for it. However, since other Time Lords refer to the machine in question as such, this more likely either a very early Retcon or Early Installment Weirdness.
 * The original series had been on for over a decade before they ever addressed the issue of The Doctor and his companions being able to understand the natives no matter what era they were in or planet they were on. When a companion actually made mention of it after having been travelling with him for several years, it was a big deal and a clue that someone was controlling her mind. In the new series, it's been brought up several times with The Doctor being unconcerned that they've noticed.
 * iCarly
 * In an early episode, Carly never takes baths because she hates sitting in her own wet dirt. Come iToe Fatcakes, her entire B-plot revolves around her having a bath and somehow getting stuck in it.
 * Another episode has Sam endure a Carly makeover to become "girlier" to impress a boy she likes. A few seasons later, Sam is revealed to have been a pageant girl for a long time, and there's no way she would've needed Carly's help to change to be a little girlier.
 * Buffy the Vampire Slayer
 * In Season 7, Spike is "tortured" by the Turok-Han by being drowned, despite the show and its spin-off, Angel, explicitly and repeatedly stating that vampires don't breathe. Apparently the First, the Turok-Han and Spike himself all forgot that little detail. The apparent Word of God is that it was supposed to be holy water; they simply forgot to add smoke and sizzling noises.
 * Whether or not vampires breathe is handled very inconsistently. Angel couldn't do CPR and survived three months underwater, but he could speak and Spike smoked. Maybe vampires can breathe but don't need to, though that wouldn't explain inability to do CPR.
 * Buffy's birthday changed a lot. Hell, it even changed once during the same episode -- the camera cut away from a computer screen displaying her date of birth, and then cut right back to it displaying another one.
 * 's presence in the season eight comics caused a continuity error: The First had impersonated him many times in season seven, but it can only take on the appearance of people who have died. Joss Whedon said that he died briefly but was revived by, but she lied and said he never died, which really just means that the writers all forgot.
 * So Weird: In season 2, Fiona has a pet cat, and has had it for some time. A long-haired cat at that. In season 3, her mother is severely allergic to cats and can't stand to be near one. (Though it is possible to develop a cat allergy...)
 * Soap: In the very first episode, Chester claims to be diabetic when Benson brings him coffee with sugar. A season or so later, trying to justify his sex addiction, he tells his wife, "If I had diabetes, you couldn't blame me for not being able to have sugar."
 * I Dream of Jeannie
 * It's established early on that genies can't be photographed. And then along comes a plot when there's a small scandal because Jeannie's been mistaken for someone else, and a paparazzi shot of her and Tony gets into the local paper. And then they go back in the wedding episode, where they have to have a plastic stand-in dummy switch with Jeannie whenever a camera is focused on them, and they end up having to steal the video that was made of the wedding. Make up your minds!
 * And speaking of their marriage, it's spelled out in a relatively early that Jeannie would lose her powers should she marry Tony, which almost causes him to marry her on the spot, until he learns that any children they have might have genie powers. Then they get married in the final season. Surprise surprise, she doesn't lose her powers.
 * And she seemed to personally know a lot of historical figures that were around in the 2000 years that she was supposed to be trapped in her bottle...
 * The Adventures of Superman has one episode in which Jimmy gives his middle name as Bartholomew, and another where a nameplate says "James J. Olsen"
 * Full House
 * In the first episode, Danny tells his mother to return to his father in such a way that implies that his parents are married. Later episodes tell us that Danny's parents have been divorced since childhood.
 * Steve's last name seems to have changed from Peters (when first introduced) to Hale (in the prom episode). Of course, before that, there was Jesse -- who had the last name "Cochran" in Season 1, but "Katsopolis" for the rest of the series. Word of God states that change was deliberate, as John Stamos requested his Greek heritage be reflected in the series.
 * An early episode shows Jesse attending his high school reunion (with a flashback taking place shortly before graduation). Several seasons later has him say he dropped out of high school (right in the middle of a class, no less) and had been keeping it a secret from everyone else. Even if this did fit continuity, it's questionable how Danny, his long-time brother-in-law, could not have known this.
 * I Love Lucy gives Ethel several different middle names, and Ricky two different first names.
 * The Office
 * Pam Beesly has had her  name in various incarnations; Pam Beasley, Pam Beesley, Pamela Jean Beesly, the now-canon Pamela Morgan Beesly...
 * Meredith went from having two kids to having one, and from being an accountant to a supplier relations rep.
 * American version of The Office:
 * On an episode of the Michael wants to throw a birthday party and asks Pam when the next birthday in the office is. She tells him the next birthday is Meredith's, which is "next month." In another episode, Jim says that it's "birthday month" and that "Kelly's was last week, Creed's is today, Oscar's is next week, and Meredith's is at the end of the month."
 * In one episode, Jim says that he's had a crush on Pam since her first day at Dunder-Mifflin. In another, he says he's had a crush on her since she showed him to his desk on his first day. Obviously, that only makes sense if they both started on the same day, but it seems odd that he wouldn't refer to it as "our first day" if that were the case.
 * Word of God -- specifically, Greg Daniels -- says that this is the writers being forgetful. He also says that he personally prefers the story Jim tells of his "worst first date", or the first day Pam started.
 * At the end of a third-season episode of Criminal Minds, Prentiss is disturbed by the case the team just solved, saying that the killer was the first unsub she worked on who wasn't a bad guy. This means that Prentiss somehow thought that the unsub from the earlier episode "Distress" was a bad guy, she forgot about him, or the writers forgot about him.
 * In one episode it is an actual plot point that Garcia had four brothers. In another, she needs an explanation of normal sibling behavior, since she's an only child. Fans Hand Wave this by pointing out she has a stepfather, so it's possible they're stepbrothers or much younger half-brothers that she didn't grow up with.
 * Hotch either married Haley directly out of high school or five years before the series starts, depending on which episode you watch.
 * The case that haunted Rossi enough to bring him back to the BAU: originally he tells it that four children watched their parents be beaten to death on Christmas Eve. When the case is actually solved, it was only three children, who found their parents' bodies, after they were killed with an ax in March.
 * In the pilot episode Gideon makes it quite clear there is no such thing as a serial killer with multiple personalities, referencing a paper he's written. Well, there weren't until they actually encounter one, and Gideon makes no objection when the possibility is brought up.
 * The first Growing Pains Reunion Show mentions that the Seavers bought a new house a few blocks from the old one, and has Carol marrying a man with a son. In the second one, Carol and her now differently-surnamed husband are expecting their first child, and the plot revolves around what is supposedly the house from the series, though given the conversion from a stagey sitcom to a realistic TV-movie, you'd be hard pressed to recognize it.
 * My Name Is Earl has a few of these mostly because of the high number of flashbacks they do, often covering very close events in the timeline.
 * The most general ones are that the Hickey brothers didn't know Joy until Earl married her and Catalina until after Earl's karmic revelation. All the flashbacks make you wonder a little why they didn't know Joy most of their lives and Catalina during the six years she had immigrated to America, as both seemed to be regulars at the Crab Shack.
 * A big one is that they established that Earl married Joy in November (six months pregnant with her son Dodge) and they had a Y 2 K adventure for their first New Years together. The last episode showed that Dodge was conceived on Halloween...
 * The Cosby Show
 * In the first episode, Claire asks Cliff "Why do we have four children?" and he answers "Because we didn't want five." Only a few episodes later, viewers are introduced to college student Sondra, the oldest of their five children. According to Word of God, it was felt to be appropriate that the couple be shown with a college-age child and demonstrate to viewers what was expected of the other children.
 * Also, in an early episode Cliff's office door shows his name as Clifford. Subsequent episodes established his name as Heathcliff.
 * Okay, we all know Mork and Mindy was pretty much just a fun show about an Amusing Alien who learns something about Earth every week, and even more so it was an excuse to have Robin Williams show off his improv. But there are just some things that cannot be excused by Rule of Funny. Such as the season four episode "Three the Hard Way" when Mork "lays" an egg out of his stomach, he reminds Mindy that he is a test tube child without a navel, and then displays the navel that was formed when the egg came out. But in the first season episode "A Mommy for Morky", Mork, mentally aged to a toddler lifts up his shirt and says "I know where my bellybutton is!". And it's there. He was already established as a test tube child, but it's there. And Mindy damn well saw it. And the writers damn well ignored it apparently.
 * The Odd Couple did multiple episodes showing how Felix and Oscar "first met." Also, one episode establishes that one of them didn't have any wedding photos; in another episode, he is seen looking at his wedding photos.
 * The BBC's Robin Hood:
 * Robin of Locksley and Guy of Gisborne meet for what is clearly the first time in the pilot episode. In season three the writers try to pull off a massive Retcon with a Whole-Episode Flashback that demonstrates that the two were young boys together. They might have gotten away with it if the flashback hadn't also included some fairly dramatic revelations: Guy's mother and Robin's father were engaged, that Robin lets Guy take the blame for a prank that nearly gets him executed, and that their parents end up dying together in a fire. The fact that neither Robin or Guy has ever mentioned any of this before is more than a little absurd.
 * A minor issue is the fact that Guy wrongly believes that he was responsible for the fire that killed his parents, even saying that it's haunted him throughout his lifetime. However, he didn't seem particularly "haunted" when he set fire to Marian's house back in season two.
 * He also claims back in season one that he's never been to a wedding before. This seems rather strange when the Flashback shows that he had a perfectly normal childhood in Locksley (though admittedly, not impossible).
 * Charmed
 * In the hundredth episode, Paige sees her own grave in an alternate universe, which states her birth as being in 1975. However, in the episode after she was introduced, she states that she last saw the nun she was taken to as a baby on August 2nd, 1977, and it's heavily implied that this was the same night her parents took her to the church to be adopted, the night she was born. Even if this implication were to be discarded, Paige's older sister Phoebe is established to have been born in very late 1975, and it's also established that Phoebe was a toddler when Paige was conceived, so they weren't twins. As such, the only explanation which makes sense is that the writers forgot the year Paige was supposed to be born in (or, of course, that in an alternate universe Paige was born nearly two years earlier and no-one mentioned it).
 * Also, in a season 1 episode, we learn that the girls' mother died shortly after Phoebe was born, MUCH too shortly after to have conceived and borne another child post-Phoebe.
 * The girls' Father was named Victor Halliwell in season 1, but later his name was Bennet and Halliwell was a name that had been passed from mother to daughter in defiance of social convention for an unspecified period of time.
 * In an early episode of Friends, Joey asks a woman when her birthday is, hoping to hit on her. When his friends object, he claims he is innocently gathering everyone's birthdays. Ross then says "Mine's December...", before Joey cuts him off, intent on talking to the girl. Several seasons later, Joey fills out a medical form for Ross, who is unable to due to a hand injury, and asks Ross when his birthday is. Ross' reply? "October 18th."
 * Monk
 * In one episode, Lieutenant Disher mentions that he doesn't have any uncles. A few seasons later, and episode revolves around him inheriting his uncle's farm.
 * In season 3, we meet Joe Christi, a former cop who tells Sharona that he was present when Monk got the call about his wife's death. The series finale depicts this scene, and there's no Joe to be found.
 * Green Acres has at least three different flashbacks to Oliver and Lisa's first meeting: one set on an ocean liner, one in which Oliver is a pilot in World War II landing in Hungary, and one in which Lisa is the daughter of the King of Hungary. The last one was Lampshaded by Oliver, who doesn't believe Lisa is related to royalty.
 * In an episode of The Suite Life of Zack and Cody, London is shown to be very competent in physical sports. In an episode of The Suite Life on Deck, she needs Zack's help. Did she leave her muscles in Boston?
 * Frasier
 * In the episode with Martin's brother, a backstory about a longstanding family feud is written in to attempt to explain why this character's never even been mentioned before -- which might work, if Martin hadn't specifically mentioned in a previous episode that he "never had a brother". It's a stretch, but it could be explained that the feud was bad enough that Martin wouldn't even acknowledge his brother's existence.
 * On a related note, the series avoided another continuity error with a fairly clever Retcon. In Frasier, Martin is a retired cop, but in an episode of Cheers Frasier described him as a scientist... and dead. When Sam Mallone stops by and notes the discrepancy, Frasier says that he'd made that story up because he and Martin had been fighting at the time.
 * In Cheers, Frasier said he had no siblings. The first episode of Frasier he meets Niles at the coffee shop and they agree to start talking again. Seems like it's just a Crane family tradition -- have a fight, pretend someone doesn't exist until reconciliation]].
 * Aliens in America has an episode about Justin's fear of performing in public - it's a plot point that he's a weak singer who freezes up so badly on stage that he wasn't allowed to sing in a school pageant that offered a role to anyone who showed up. A few episodes later, Justin's been a soloist in the school choir for years.
 * Young Blades: When Jacqueline meets The Great D'Artagnan in "Secrets of the Father," she excitedly goes on about how she used to swordfight with her brother while pretending to be The Great D'Artagnan. D'Artagnan (his son) clearly hears this and doesn't seem to be surprised or care. But several episodes later, in "Secrets," Jacqueline is suddenly very embarrassed about pretending to be The Great D'Artagnan and doesn't want D'Artagnan to know about it. When he overhears, he teases her about it. Neither of them seem to recall him finding out about it before.
 * In season one of Boy Meets World, Mr. Feeny informs his students that they will be the high school class of 2000. The characters actually graduate five seasons later, in 1998.
 * The X-Files: In Season 1, Mulder describes the abduction of his sister, saying he couldn't see what was happening due to paralysis which prevented him from turning his head. In the season 2 premiere, the abduction is shown in a flashback, and young Fox is looking right at her as she floats out the window.
 * Mulder claims to be red-green colorblind in an early episode, yet doesn't seem to have any trouble noticing what's odd about the green blood shed by an alien bounty hunter in a later season.
 * That '70s Show
 * In the first episode, we learn that Eric and Donna have lived next door at least since age 4. In a later season, a flashback shows their first meeting, at age 8. Also, Jackie is established in the first season as a sophomore, and the other characters as juniors in 1976. Five years later the characters all graduate at the same time. Three years after that, they all say goodbye to the 70's on New Years Eve, 1979. If not for the Halloween/Thanksgiving/Christmas episodes, you could say that each season represents less than one year of the characters' lives...
 * In the second episode, we meet Donna's sister Tina, who is never seen or mentioned again.
 * Wonder Woman TV Series: The pilot establishes that Paradise Island, at 1942, is a Hidden Elf Village of Hot Amazons who had never seen a man in a thousand years. Princess Diana is elected The Champion to travel to Men’s world. She is the first amazon to left Paradise Island in a thousand years. However, in third season’s episodes Diana's Disappearing Act,Cagliostro claims that Wonder Woman has stopped all his lineage plans since the original Cagliostro (born in the 18th century) and in Screaming Javelins, Diana remembers to have meet Napoleon Bonaparte, implying not only that she was in Europe those years, but that she was already doing her superhero job.
 * Sex and the City - early in Season 6, Carrie is shopping with Samantha and tells her, "I don't buy furry shoes;" Carrie bought near-identical shoes (maxing out her credit card and allowing a friend to pay for them, no less) in Season 1. It wouldn't have been so painful but for the perfect storm it landed in: beginning of popular internet fandoms, resurgence of popular Long Runners, beginning of DVD box sets in Season 1 - the fandom was livid.

Myths & Legends

 * Older Than Feudalism: Myths were bodies of multiple stories by multiple authors, spread out over entire countries, over centuries or millennia. It's no surprise that there were many versions of each story, and that the stories were changed over time by the needs of authors and audiences. Every single established mythology has multiple versions with a crapload of contradictions. That's what you get from lengthy oral traditions and people living a long way from each other. It's like a huge game of Telephone, splitting and spreading constantly. Only thing that can bring it out are written records and halfway decent communication systems.
 * See the origins of gods in Greek Mythology.
 * Aphrodite both rose from foam created by Cronus's severed testicles and was born to a mistress of Zeus.
 * Dionysus is both the son of Zeus, and the son of Persephone and Hades.
 * One day Zeus had an agonizing headache, and when Hephaestus split his head open to relieve the pain, Athena sprang forth. She went on to become the most important goddess of her generation, and Zeus took great pride in the fact that he'd "fathered" her all by himself. Hera became jealous and gave birth to a child all by herself, to prove Zeus wasn't the only one who could do it. That child? Hephaestus. (Some authors solved this one by having somebody else, like Prometheus or Hermes, split Zeus's head instead, or denied that version of Hephaestus's birth.)
 * The Canon of Norse Mythology consists of numerous sources which contradict each other on many points. In particular, the important story of Balder's death exists in two very different versions.
 * Many myths like these take place in the undefinable time of legends, when the world wasn't quite ready and things like action and consequence didn't necessarily happen in normal order. That's also why legends where someone eats or steals away the Sun explains all the subsequent eclipses, even though it was supposed to happen a long time ago.

Tabletop Games

 * The Demon Queen of Spiders, goddess of the drow, is called Lolth. R.A. Salvatore accidentally spelled her name Lloth when she became a Forgotten Realms character, and the error proliferated to the extent that a rationalization was needed.
 * Juiblex had similar problems, being often misspelled as Jubilex. Since both are Demon Lords it is quite easy to invoke I Have Many Names to justify the differences.

Toys

 * Bionicle
 * The original intro of the story involves Takua summoning the Toa in their canisters to the island. He got blasted into the sky to witness six metal capsules descending form the "heavens" and landing in the sea, then drifting to the island shores. Later material explained that these canisters had been floating in the ocean for a thousand years before Takua attempted to do this.
 * Another example is what the Order of Mata Nui reported about Karzahni. In their book, they write about how he is amassing an army in his own realm to lead them into battle. When Karzahni reappears in the story, he reveals he's been following the Matoran who later became the Toa Inika ever since they had gotten away from him, so he would've had no time to train any army.

Video Games

 * Ratchet and Clank Future: Tools of Destruction reveals Ratchet to be ... but in Going Commando, Whoops. Apparently, Word of God has said . Regardless, in the prison in Tools of Destruction, they mention
 * Pokémon
 * Which came first? Mew or Arceus? It is commonly explained that Arceus created Mew, as the legend states that Mew is simply the common ancestor of all Pokémon. Scientifically speaking, it's easy to understand by studying evolutionary lines why humans would never actually trace things back to Arceus, since Arceus was never a part of the evolutionary line. So, to humans, Mew was the first Pokémon until Arceus was discovered much later. More of a Retcon.
 * Another aspect that people outside of the 'verse overlook is the fact that, while evolution has been scientifically traced back to Mew, Arceus is a legend. If you think about it, any trainer who catches Arceus is basically providing their world's first ever piece of conclusive evidence for the existence of God.
 * In Kingdom Hearts II, we're told that King Mickey was the one who banished Pete from his kingdom permanately for a heinous act, but Birth By Sleep shows us it was Queen Minnie who banished him under a set time limit for being a bad sport.
 * In Street Fighter II, Guile wants revenge on M. Bison for killing his friend Charlie. In Street Fighter IV, he's insistent that Charlie is still alive because (as established in the Street Fighter Alpha prequel series) they Never Found the Body.

Web Animation

 * Red vs. Blue: Word of God says Grif was the Army's sole draftee, and his resentment of it drives him to be the world's biggest slacker. However, in the first episode, he says he "signed on to fight some aliens".

Western Animation
""They never said 'Star Trek,' they said 'Start Wreck!'""
 * Goof Troop
 * In spite of the fact that it is established that Goofy hadn't seen Pete or Peg since graduation, and that Max and PJ only met at the age of twelve, after Goofy returned to Spoonerville and moved in next door to the Petes, several episodes make references to Max growing up in Spoonerville. And in the Christmas special, Pete declares that every year Goofy wrecks stuff, although that should technically have been Goofy and Max's first Christmas in Spoonerville.
 * Max's first Christmas maybe, but as stated, Goofy lived in Spoonerville. Presumably, that's when he always messed up Christmas. Statements about Max growing up in the town, however, do appear to be this.
 * Then there's the question of whether or not the movie spinoffs, A Goofy Movie and its sequel, can even be said to be in the same continuity. Somehow in the space of a few years Pete seems to have lost his wife, his daughter, his auto dealership, and developed a completely different relationship with his son. And Max has gone from being a popular kid to a loser. And lives in a different house. No mention is made of any of these things.
 * Just a few of the more famous ones from the Transformers franchise:
 * A total list of all instances in Transformers Generation 1 would fill a library, as continuity wasn't considered to be terribly important. Autobots fly! Now they don’t! Surprise, I have a built-in tool to solve today’s problem! Now I don’t! However, there are a few that do affect the big picture:
 * The Constructicons. Their introduction discusses the Decepticons building them in the caves they were in at the time. Omega Supreme’s backstory, however, involves how the already-existing and formerly good (ignore the Decepticon symbols already on them, please!) Constructicons were turned evil by Megatron. Megatron’s backstory? He was created by the already-existing, already-evil Constructicons! That’s three Constructicon origins, none of which are at all compatible with either of the others.
 * The Matrix of Leadership. The powerful artifact containing the wisdom of all past bearers and other mysterious properties as needed has been in Optimus’ chest all along? There was no sign of it when he took major damage to the area it was eventually shown to be held in, and some people still aren’t buying it.
 * In The Movie, Unicron turns Skywarp and Bombshell into two identical robots that he refers to as "Cyclonus and his armada." A second Cyclonus is a rather poor "armada..." and only one Cyclonus is ever seen again. Who became Cyclonus and what happened to the other? Good question. (Oh, and Bombshell is seen again, not as Cyclonus. Voiced in-character, so not one of TFG1's zillions of "oops, we used the wrong animation model" cases.)
 * The Coneheads are explicitly destroyed twice, and are just there again next time, without comment.
 * As stated before, those are the biggies, the ones affecting continuity (in a show that's pretty episodic). Rare is the G1 episode that doesn't have something in this category. Not that the other series are completely innocent, but G1 episodes were often rushed, and not checked for things like this, resulting in errors at the macro (Constructicons) and micro (Ironhide goes to van mode and is robot mode in the very next shot and stays that way) levels being ridiculously common.
 * And, of course, the Unicron Trilogy, a dub of three series that were originally a duology and an independent series. Calling it a continuation makes Transformers Cybertron a continuity headache, where characters who were dead are back without comment (or, in Sideways’ case, without anyone remembering him.) and a great many characters who were important never turning up again, and a couple of returning characters having radically different personalities, most glaringly Wing Saber. The Masquerade is in effect and only Agent Franklin suspects there’s something to the “alien robots” thing, though humans have known of, and worked alongside, Cybertronians for years as of the previous series. That’s by no means the whole list of inconsistencies. Read the supplementary materials if you want it all “explained” in a way that arguably makes it all worse.
 * In her first episode in The Replacements, Celebrity Star is arranged as Shelton's girlfriend, because she likes out-of-shape, whiny nerds like him. She proves too clingy and oppressive for him... and finally dumps him when he proves to be a middle-school hunk without his glasses. Her next appearance has her making a movie intended to ruin his reputation for dumping her.
 * Recess
 * The Vague Age of the cornchip girl. She appears to be in first or second grade, but spends most of her time with the kindergarteners, and during the Picture Day episode, she's not shown among the crowds having her picture taken.
 * Not to mention, Gus being the new kid in school in fourth grade, yet somehow also appearing in Kindergarten. As well as how he appears to be attending school at the time of the Great Jungle Gym standoff (This can be attributed to an animation goof; since he doesn't have any lines). This is addressed in one of the latter episodes. Apparently, he did spend some time in the same kindergarten as the others, but being little children, they had forgot.
 * Also, The Ashleys are shown to be in another class in the Can Drive episode -- yet several other episodes show them sitting in the exact same class as the main gang.
 * King of the Hill
 * The episode "Life: A Loser's Manuel" is chock full of them. First of all, in the very first episode, Luanne is eighteen years old and she has just moved into the Hill's home after her mom stabbed her father with a fork. In a later episode "Luanne Gets Lucky", she claimed she was sixteen when the event happened and had to miss her prom because of it, and yet in the first episode mentioned her dad said she was just a little girl the last time he seen her and Luanne seems to have no memory of the event despite the previous episode taking place one season earlier. Later on, Hank mentioned that he had never met Peggy's brother despite in earlier episodes he mentions what a great man he was and how he enjoyed his company, and last of all in earlier episodes Hoyt Platter was said to be a small, timid, nerdy man who looked like a male version of Peggy and ran off because his wife Leanne was abusive to him, yet in this episode he is depicted as a morbidly obese man who looks nothing like Peggy, is a total Jerkass, and he mentions that he ran off because of a drug addiction and the possibility that he'll be in jail for the rest of his life if he commits one more crime (which he tries to cover up from Luanne as "working in an oil rig").
 * Another episode dealt with Peggy not having spoken to her mother in twenty years and having to save her mother's ranch from being taken down; however, in a much earlier episode, Peggy's mom had a completely different appearance and personality, a fine relationship with her daughter, and not owning a ranch.
 * Even worse than that, early episodes have Peggy and Hank as high school sweethearts from rival schools and implies that Peggy's family lived i Texas for a decent amount of time yet the above mentioned ranch episode says Peggy grew up on the ranch.
 * In a season 13 episode, Cotton tells Hank, via audio recording, to flush his cremated ashes down the same bar toilet that General Patton's ashes had been flushed down, the same as the rest of Cotton's dead war buddies, but in a season 4 episode, Cotton fought with Peggy's help to be buried in a Texas government cemetery, and succeeded. Though given Cotton's Jerkass nature it could just be one more screw you to Peggy.
 * Joe Murray has said that any flashback contradicting another flashback on Rocko's Modern Life is just the result of people misremembering or exaggerating things, not unlike in Real Life. Thus, Filbert remembering being in high school with Rocko, in spite of Rocko having just moved to the States recently, is just Filbert misremembering.
 * Duckman
 * The show features several conflicting flashbacks depicting how Duckman and Cornfed first met.
 * Season 1's "Civil War" has them meeting in a store Cornfed worked at, with Duckman being an obnoxious customer that he saves three times from a robber.
 * Season 3's "The Girls of Route Canal", however, shows Duckman encountering Cornfed years earlier at an airport while looking for Beatrice. This one was explicitly a subversion played for laughs, as Cornfed attempts to introduce himself and help Duckman, but the mallard is in full Jerkass mode, so he barely even acknowledges him outside of insults.
 * Finally, Season 4's "From Brad to Worst" shows them as long-time friends in high school. The writers may've been aware of the error, but this one was not played for laughs.
 * To list all of The Simpsons series continuity errors would take forever and a day. Because TV Tropes loves you (and doesn't want to waste time, space, and bandwidth), we're going to list only the most egregious examples (if they begin taking over the page, the section will be split off to its own segment).
 * In the episode "Lisa's Wedding", Maude Flanders is clearly visible at the wedding fifteen years into the future, even though Bart and Lisa are still children when Maude dies in "Alone Again, Natura-Diddly". Probably justified that the wedding story was being told by a gypsy reading tarot cards, and so was only making guesses.
 * Worth noting said episode depicted college-age Lisa and the rest of the similarly aged Simpson family and supporting cast in the waaaaay distant future of... 2010.
 * Also, the street address of the Simpsons' house. From the very first time the address was brought up (the episode "Blood Feud"), it was Evergreen Terrace. However, the house number was 94 rather than 742. Subsequent references are inconsistent on the number, and "Kamp Krusty" even gives the street as Spalding Way. "Marge in Chains" finally establishes the address as 742 Evergreen Terrace, though it briefly went into relapse in "Homer the Vigilante" by giving the house number as 723. Interestingly enough, the address "742 Evergreen Terrace" was originally given to Snake's cattle rustling shack.
 * The Whole-Episode Flashback "And Maggie Makes Three" reveals that Homer had to renounce his dream job at the Bowl-A-Rama and return to his position as safety inspector in Burns's power plant when Maggie was born. This contradicts Season 1 "Homer's Odyssey", where Homer was a technical supervisor before being fired and rehired as a safety inspector (and he already had 3 children, obviously).
 * Also in "And Maggie Makes Three," Homer's reactions to Marge being pregnant (yelling "You're pregnant!" and "You're pregnant again!" while ripping his hair out and running screaming from the room) were WAY different than what was depicted in "I Married Marge" (from season three) and "Lisa's First Word" (from season four). In "I Married Marge," Homer found out Marge was pregnant when she called him from her job as a skating waitress at a diner and Homer squeezed his tube of cookie dough (which he was eating with Barney while the two were watching Charlie's Angels) in shock and when Dr. Hibbert confirmed it with, "Well, Miss Bouvier, I think we found out the reason why you've been throwing up in the morning. Congratulations, Mr. Simpson," Homer yelled, "D'OH!" so loud that a man in traction commented on it. In "Lisa's First Word," Marge told Homer outright that she was going to have another baby (after Homer wrongfully guessed that he and Marge were going to start having sex in the morning) and Homer was ecstatic -- until Bart flushed his car keys down the toilet.
 * Aside from that, the above scenes of Homer ripping his hair out take place in the Simpsons' current house, which they didn't move into until Marge was pregnant with Lisa.
 * "The War of the Simpsons", a second season episode, has a flashback of Bart as a baby driving the car in front of their current house.
 * In "Homer Simpson in: Kidney Trouble" (season 10), it's implied that Grampa has (or rather, had, thanks to a "kidney blowout") two kidneys. In the season two episode "Old Money," Grampa told Bea (his short-lived girlfriend) that he only had one kidney.
 * While Lindsey Naegle does change jobs surprisingly often (due to the fact that she's a sexual predator), it seems rather odd that she's been shown as a leading member of Springfield's Republican and Democratic Parties in separate episodes.
 * In "Lisa the Simpson," it's revealed that the men in the Simpson family get dumber as they get older while the Simpson women remain smart. There are a couple things wrong with this:
 * Homer's half-brother Herb (voiced by Danny DeVito) apparently is immune from this (or the writers forgot that he existed), as he had his own car company (until he hired Homer to design him a new car), then got rich by inventing a machine that translates baby babbling. Then again, Herb could have gotten his smarts from his mom's side (his mother being the carny woman who ran the dunk tank and has sex with Abe for money).
 * The season 12 episode "HOMR" revealed that Homer actually is smart (or at least of average intelligence), but became dumb when he shoved a bunch of crayons up his nose and one got lodged in his brain.
 * If Bart really is destined to be stupid, how is it that he was able to make a science project that won over Lisa's ("Can hamsters fly planes?") in "Duffless," and trick adults into doing what he wants? The same thing with Grampa Simpson: it's been shown that he was a strong, competent military officer during World War II (then again, the season four episode "Lisa's First Word" revealed that he really doesn't know anything and got by in life on his looks until they withered away like an old piece of fruit, and that he bought his house by naming names during the 1950s Quiz Show scandals).
 * Codename: Kids Next Door: In a show with surprisingly good continuity, "Operation: College" has the other kids kidnapping Numbuh One from Professor XXXL, and not even batting an eyelid when XXXL says he's using Numbuh One for his snowcone research... even though his snowcone research was the plot twist of his previous appearance ("Operation: Arctic").
 * Arthur
 * In an episode, Sue Ellen is seen in a Kindergarten class photo when in fact she transferred in third grade.
 * In another episode Muffy was shown in a kindergarten flashback but she moved to Elwood City in the second grade.
 * Futurama
 * In season 4; it is established that talking about Star Trek is illegal, although numerous references to it were made in the first three seasons, including a fictitious movie that was nominated for an Oscar for Best Product Placement (and on top of that, Leonard Nimoy from the original Star Trek series is in the celebrity head museum . In the first episode, he was a greeter, but in "Where No Fan Has Gone Before," Nimoy is now on one of the main shelves). Lampshaded on the DVD commentary.


 * In the pilot, Bender claims that "I don't need to drink, I can stop anytime I want!" This contradicts the fact that robots in Futurama are powered by alcohol, established in episode three, "I, Roommate".
 * In season 3, the professor specifies that there exist only two parallel universes (the other one seems to be the same as this one except that everyone wears cowboy hats). In season 4, an entire episode revolves around jumping through multiple parallel universes. But perhaps one can argue that the professor's machine had created all of those universes, rather than just a gateway to them. Word of God Hand Waved this by saying that the cowboy universe was really the only parallel universe and the others were perpendicular universes.
 * Bender has mentioned being able to remember his own "birth." In season 6, it is revealed that  was the inspector who approved him on the assembly line, but Bender does not remember that event.
 * Versions of his Birth are also pending to changes. In the episode where he recounts his birth, it was shown that he was built the way he was at that moment in a robot factory in Mexico. In another episode, where the cast turns into babies, Bender slowly de-upgrades along with everyone else, shrinking with each successive step just like everyone else. On top of that, he mentions he's only 5 years old, yet shrinks with everyone else in the aforementioned episode. If he really was 5 years old, he would have disappeared in the goo and never came out (since everyone gets around half a decade younger almost instantly), much like one of the buds on Zoidberg's body.
 * In the season 6 episode "Lethal Inspection", Bender discovers that he was built without a backup unit that would download a copy of his programming (i.e., his "soul") onto another robot body. Yet on the later episode "Ghost in the Machines", Bender dies and becomes a ghost, able to possess any machine.
 * Also in "Ghost in the Machines" we meet Robot God. This does not contradict anything in the series but it does contradict several audio-commentaries on past seasons where Matt Groening and the writers repeatedly stated that there is no Robot God.
 * The Grim Adventures of Billy and Mandy: Grim becomes the Grim Reaper on at least three separate occasions. To list them: When his parents told him it was his "destiny" as a child and forced him into it, despite his desire to sing; found out his true calling, also as a child, but kept up the image of being a country rocker for over a millenia to please his father, and got the 'once in an eternity' school election to be one, competing with The Boogey Man and his old Childhood Friend from Wrath of the Spider Queen. The probably only concrete thing about his reaping origins (at least in two of them) is that he started doing it as early as cavemen and/or dinosaurs.
 * The Total Drama Island series has this fairly often.
 * One episode, for example, claims that Lindsay has very large feet (that we never see) when she takes off her (apparently very tight) boot. However, we see her barefoot in the TDI Playa des Losers episode, and it's as small as you would expect it to be.
 * During the TDI special, Chris says that Owen is the youngest of three brothers. In Action, Owen gives anecdotes about his two younger brothers.
 * A lot of information about the characters comes from their online bios, but the show seems to contradict them fairly often. Similar to Owen, Geoff's bio says that he's the oldest of five brothers, while on the show he once mentions having at least one older brother. Trent's father is supposedly an accountant, but on the show he says he's a lawyer (maybe he was lying to avoid eating that garbage?) There are at least hints of this in other places, like Harold supposedly having an older brother and a younger sister, but alluding to his sister as having psychology books as if she were in college.
 * SpongeBob SquarePants
 * An episode has Patrick being visited by his sister, Sam. The problem with this is that he said back in season 2's "Something Smells" that he did not have a sister. Then again, this is Patrick we're talking about...
 * The episode where Squidward becomes nice has Squidward actually beating SpongeBob for Employee of the Month at the Krusty Krab. The problem with this is that, in The SpongeBob SquarePants Movie (which is the chronological series finale according to the creator), SpongeBob says he has won that award 374 times in a row.
 * In the Disney animated series Hercules, Hercules and Hades always run into each other every other episode, despite the fact that in the film this series is based off of, Hades isn't even supposed to realize Hercules was still alive until the latter is an adult. While a continuity error, this actually makes more sense than the movie due to the plot hole that goes along with it... how on Earth could the lord of the dead not be aware that Hercules wasn't dead?
 * Similar to the SpongeBob example above, The Fairly Odd Parents episode "Double-Oh-Schnozmo!" introduces Cosmo's brother Schnozmo, despite that the earlier episode "The Gland Plan" said that Cosmo didn't have any siblings.
 * Happens a lot on American Dad, but most can be dismissed with the Rule of Funny.
 * In "42-Year-Old Virgin", Stan claims to have never killed anyone, but he broke Jay Leno's neck on "Stan of Arabia, part I", killed his co-worker's double at the beginning of "It's Good to Be Queen", accidentally disintegrated one of his other co-workers in "I Can't Stan You", shot down a hang glider in "An Apocalypse to Remember," and shot a painter in "Con Heir."
 * However, the episode "Haylias" ends with Stan suffering from evident selective memory loss following his battle with the Brainwashed and Crazy Hayley, which could explain his assertion that he has never killed anyone as "Haylias" aired on American TV before "The 42-Year-Old Virgin."
 * Another possibility is that Stan has never killed anyone he was assigned to kill, since all of the murders he committed were accidental.
 * The first season develops Roger's experience with the outside world and learning to use disguise, but later episodes (particularly "Weiner of Our Discontent" and the first Christmas episode in which Stan goes back in time to kill Jane Fonda to rid the world of the wave of political correctness that has ruined Christmas) show that Roger has been disguising himself and living among humans since the 1950s (he protested against the integration of a Southern college in the 1960s by knocking the schoolbooks out of a black girl's hand, popularized disco in the 1970s, auditioned for the role of Vicki the robot in 1984, and was the contributing factor to Joseph Hazelwood crashing the Exxon Valdez and causing that oil spill in 1989, Biggie Smalls getting shot and killed in 1997, and George Lucas introducing the world of Jar Jar Binks near the end of the 20th century), perhaps even longer, since one episode revealed that Roger knew Stockard Channing in the 1940s when she was 50 (even though Stockard Channing was born in 1944).
 * In "Of Ice and Men", Roger doesn't know what happened to Stan's skating partner, though "Roger 'N Me" shows that Roger probed Stan and now has all of his memories. Either the writers forgot about that part or Roger just doesn't care about anyone who's not him (which is par for his character).
 * In the pilot episode, Roger (after getting sneezed on) sarcastically says he's supposed to bring pneumonia back to his planet, but in the second episode, Roger claims that his species is immune to all human ailments (except for an unexplained cold sore). On top of that, "Weiner of Our Discontent" reveals that.
 * In "Of Ice and Men," Toshi (the Japanese kid) marries the Russian bride, but an earlier episode (forgot which one) revealed that Toshi isn't worried about getting girls to like him as he has a girl arranged to be married to him back in Japan. Then again, the Russian bride's mysterious disappearance after the episode could be the writers remembering that (or just making it so that way Toshi is as much of a loser with girls as Snot, Steve, and Barry are) and correcting the mistake.
 * In "Brains, Brains, and Automobiles," Francine teaches Roger how to use the vacuum cleaner, even though Roger had used one before in "Not Particularly Desperate Housewives" (even though the vacuum was rigged to explode by the Ladybugs). On top of that, Roger already knows how to clean a house (as seen in "Helping Handis").
 * The episode "Chimdale" reveals that, but a lot of earlier episodes have shown that.
 * In the season two episode "It's Good to Be Queen," it's revealed that Francine's favorite song is "Little Red Corvette" by Prince, but in the season one episode, "Francine's Flashback", Francine's favorite song is "The Greatest Love of All", by Whitney Houston (whom Stan personally brought over to sing to Francine in exchange for crack cocaine). It is possible that Francine can have two favorite songs, but for the purposes of continuity, the writers should have stuck with "The Greatest Love of All" as Francine's favorite song since that was revealed first.
 * In the episode "May the Best Stan Win," there is a tombstone that reveals that Stan was born in 1967 and Francine was born in 1971, making Stan four years older than Francine, but the season one episode where Hayley dates Stan's boss reveals that Francine is actually ten months younger than Stan. This also throws Francine's continuity out of whack, since it's been stated that she was a wild teenager in the 1980s. If Francine really was born in 1971, she would have been nine in 1980 and wouldn't reach teen age (13) until 1984 (even though the episode "Francine's Flashback" shows that Francine looked at least sixteen in the mid-1980s when she first met Stan).
 * In the season two episode "Star Trek" (in which Steve becomes a children's book author), Steve is horrified and disgusted when he finds out that the centerfold model Stan promised him is an old woman (and that the picture of her when she was young was from 1957), but in season one's "Con Heir," Steve had no problem making out with and having a romantic relationship with an elderly woman at a nursing home.
 * South Park
 * In the episode "Cartman's Mom Is Still a Dirty Slut (2)", Kenny comes back to life by magically reappearing and the characters (at least Kyle) are shown to be aware of this. In the episodes "Cartman Joins NAMBLA" and "Coon Vs. Coon And Friends" Kenny comes back to life by being reborn through his mother and the characters are unaware of him dying. Rule of Funny doesn't work on this because Negative Continuity was played seriously in CVCAF.
 * A few episodes mention that Kyle's family moved to South Park when he was about three. In "It's A Jersey Thing," however, it's a plot point that they moved there while Sheila was pregnant with him. (Though Kyle only says that he was born "here," so maybe he meant somewhere else in Colorado?)
 * There have been several examples of minor characters' names changing, and even more important secondary characters have inconsistent surnames (Token Williams becomes Token Black, Jimmy Swanson becomes Jimmy Valmer, etc.)
 * At the end of the Cars short Tokyo Mater, Kabuto is stripped of his modifications as a result of him losing to Mater in a drift race. However in Cars 2, Kabuto somehow got his modifications back! That is, if Tokyo Mater actually happened. And Kabuto could have easily regained them in the multi-year time gap between them.
 * Winx Club
 * The worst example: Nabu. He in season four, episode 24. Yet, two episodes, he's at the Frutti Music Bar watching the Winx's last performance.
 * At the end of season four, the Winx are back in their Enchantix forms. It remains to be seen if that was an error, but in the very least, they're still Believix fairies in Magical Adventure.
 * Clarice, the troublemaker from episode one of season four, appears to be a first-year student who has never seen the Winx before. But she and her friends were in season three and Secret of the Lost Kingdom.
 * Magical Adventure might as well be considered a separate canon.
 * At the beginning, Sky proposes to Bloom in Domino's palace garden. But he already proposed her at the ball at the end of The Secret of the Lost Kingdom.
 * Nabu.
 * The Nickelodeon TV movies summarized seasons one and two and created a few continuity errors because of time constraints.
 * Stella was originally "the fairy of the sun and moon" because of her parents, the sun king Radius and the moon queen Luna. But Nickelodeon redubbed her "the fairy of the shining sun." Yet, in season three, Countess Cassandra tells Chimera she would make "a better princess of the sun and moon" than Stella would.
 * In the original series, Professor Avalon was . But "The Shadow Phoenix," he was . This broke continuity with season three, since Avalon was teaching at Alfea.
 * Family Guy
 * Stewie in the episode "Forget-Me-Not" put Brian and Peter under a simulation to see if the two were truly loyal to each other and it was shown that they are after . However, "New Kidney in Town" revealed that Brian was willing to donate a kidney to his friend Peter (who needed one after suffering kidney failure from a homemade energy drink). That's pretty loyal, no?
 * An early episode contains a flashback to when Stewie was younger and he had a normal-shaped head. He was jumping on the bed, smacked his head into the ceiling, and squished it into its trademark football shape. In another episode there's a flashback to when Stewie was born and he already had the football head.