Clash of the Titans/YMMV

The 1981 original

 * All-Star Cast: Zigzagged. The Olympian Gods were all portrayed by actors who were, at the time, A-list in Britain, the most well known being Laurence Olivier. Almost everyone else in the film was an unknown.
 * Fridge Logic: See here.
 * Ham and Cheese: Burgess Meredith as Ammon. A reviewer even said he acts as if he's in a Mel Brooks movie.
 * Partially justified, as Ammon is a theater actor. Theatricality is expected of him.
 * Special Effect Failure: The stop-motion is mostly effective. The bluescreen isn't (Poseidon opening the gates being the worst offender). And while folks often dismiss this with a "hey, it was 1981, FX was crude back then" they forget that Jason and the Argonauts (with the magnificent stop-motion battle with the skeletons) was released almost 20 years previous.
 * Visual Effects of Awesome: The scene with Medusa is probably Ray's best work.
 * What an Idiot!: Queen Cassiopeia, for comparing her daughter's beauty to Goddess Thetis right when she's standing very under her statue.
 * Woobie, Destroyer of Worlds: Calibos can be perceived sympathetic and at least worthy of pity, especially because we are only informed of his cruelty before the transformation.
 * Of course, he also demonstrates a fair bit of cruelty and violence post-transformation, and his nightly abduction of a sleeping Andromeda is distinctly creeptastic.

The 2010 remake and sequel

 * Anvilicious: Alright, Mr. Leterrier, we get it. Men don't need gods. Is it really necessary to remind us of that every ten minutes though? On the other hand, perhaps its just a bad case of the studio thinking Viewers are Morons.
 * Non Sequitur Scene: If you've never seen the original you might be asking yourself what a futuristic robotic owl is doing laying in the bottom of a trunk in ancient Greece.
 * Either way greatly stressing the Fourth Wall and Willing Suspension of Disbelief.
 * Actually Older Than You Think: the futuristic robotic owl is actually mentioned in Greek myths (I don't recall if it is in the myth of Perseus or others) as a creation of Hephaestus gifted to Athena. And if you think the greeks where ahead of their time with the robo-owl wait till you find out about the two female assistants Hephaestus made for himself, out of chromed steel.
 * The conversation that young Perseus has with Spyros about his anxieties regarding the new baby and Spyros not being his biological father. It has no bearing on the plot except to set up a character who is killed a few scenes later without so much as a single line. You really have to wonder why they bothered with either one.
 * In the sequel, when Perseus, Andromeda, and Aginor enter Tartarus, Andromeda thinks she sees Korrina, the soldier who prayed to Ares, walking around, while Perseus appears to see his son, Helius. Unless I'm missing something here, what was that all about?
 * Hallucinations.
 * The minotaur as well. It turns up, gets killed and is never mentioned again.
 * Draco in Leather Pants: Proving that giving a villain any minor amount of sympathy will make at least part of the audience decide he's the true hero of the story, Hades. And while Medusa's backstory is even more tragic (mostly to drive home yet again how much the gods suck), audiences in a hurry to paint her as a poor hurting woobie who just wanted to be left alone tended to ignore her cackling glee as she tormented and slaughtered adventurers.
 * Hijacked by Jesus: Hades is a villain who wishes to unleash "hell on earth" and must be defeated by Perseus. Given that the original myth specifically states that Hades helps Perseus on his quest (giving him the invisibility hat), and that in the fables Hades was perfectly content with his position (the only qualm he seems to have had was how boring the underworld could be at times), and is one of the few Gods who is borderline decent. Never mind that in Greek lore, the actual Titans actually were imprisoned in Erebos—a wing of the underworld—for some time. The film makers could have arranged Kronos or Iapetos to be usurping Hades and waging war from there, which would have made a lot more sense.
 * That woman he kidnapped? He married her. And they're the happiest couple in the entire pantheon.
 * Hades' domain also includes the Elysian Fields. Read: Paradise.
 * Luckily the sequel came to the rescue.
 * The Load: Andromeda in the sequel. Perseus and Agenor do all the work. Perseus has to rescue her at least three times. The only thing close to helpful that she does is charm Hephaestus into helping them.
 * Memetic Mutation: "RELEASE THE KRAKEN!"
 * Special Effects Failure: While the special effects in the film were pretty much Visual Effects of Awesome, the half-assed converted 3D conversion certainly applies.
 * Strangled by the Red String: The alternate ending from the Blu-Ray is closer to the original in that Perseus and Andromeda fall in love... even though they barely share screentime together due to Andromeda being Demoted to Extra, Perseus is a Darker and Edgier hero than the "motivated by love" original, and the rest of the movie builds up a different love interest in Io.
 * Surprisingly Improved Sequel: Could be caused with the Critical Dissonance
 * Unfortunate Implications: The (Arabian) djinn distracts Medusa by blowing himself up.
 * They Wasted a Perfectly Good Plot: There were times when it felt it they were setting up to deliver the message "just because they're your children/you created them doesn't justify abusing them," but it never happened.
 * Tough Act to Follow: Naturally, a big reason this film didn't do well is because everyone compared it to the 1981 version.
 * What an Idiot!: And to think...if Hades hadn't gone out of his way to be a dick by, he would have been able to pull of his plan to seize power without a hitch.
 * If the Harpy that stole the bag with Medusa's head in it had say, dropped it in the sea, or fed it to the Kraken, Hades would have won straight off.
 * They could have turned right around and, you know, used it on Perseus. Just saying.
 * If Perseus had just gone with Zeus when he asked him to in the sequel, he probably could have stopped Ares and Hades from imprisoning Zeus in the first place. What's worse is that he makes a big deal out of not leaving his son's side...and then five minutes later, leaves his son's side and a Chimera attacks his village, nearly killing the both of them. Brilliant, Perseus. Brilliant.
 * Woobie, Destroyer of Worlds: Medusa in the remake. Rape victim, cursed by a Goddess of Wisdom for being raped, and sent to the underworld to dwell in squalor. Is it any wonder she spends her time gleefully hunting any man stupid enough to try to kill her?
 * Visual Effects of Awesome: Painfully averted with the slapped on 3D, but the Kraken looked freaking awesome.
 * The sequel's special effects are spectacular, most notably Kronos, who's essentially a walking volcano of death and destruction. He's truly a sight to behold.