Monster Progenitor

The original member of a line of monsters. Thus the oldest, and, often, the strongest of the line. Likely to be the top Monster Lord. In some settings it is possible that killing him would cause all of his line to be exterminated (or, if each of those monsters Was Once a Man, return them to normal). It is common for the Monster Progenitor not to have the Kryptonite Factor or Weaksauce Weakness of his descendants.

Just how the Monster Progenitor came to be can vary. Maybe he has always been, or was created by god. Maybe he Was Once a Man and was cursed or changed. Similarly, how he reproduces can vary. Maybe he does it the old fashioned way, or via The Virus, for which he is Patient Zero.

Dracula is very often made into the Monster Progenitor of vampires.

Related to Mother of a Thousand Young. Unlike her, however, the monster progenitor always is the same species as his descendants. He may be tougher, but he shares many of the same basic traits, while Mother of a Thousand Young may have nothing in common with her descendants.

The biological equivalent of Super Prototype. Related to Hive Queen, Mother of a Thousand Young and Stronger with Age. Also known as First of Its Kind, making it the exact opposite of Last of His Kind. If his death destroys his children, he may be the titular keystone in a Keystone Army.

Dracula as Original Vampire

 * The original Dracula is this, of course. It's known he's the original vampire of his line of vampire, but not if he is the first ever vampire.
 * Dracula in Blade Trinity is said to be the ancestor of all vampires. Of course, he's also the strongest. Blade's Dracula (AKA Drake) is not only the strongest but is also immune to any vampire weakness and can make himself look like anyone.
 * Ditto for Dracula in Van Helsing.
 * Ditto again for Alucard from Hellsing, who is said to be the first vampire.
 * Jared Nomak, the progenitor of the Reaper strain in Blade II, is also immune to all but sunlight. His heart is protected by a hard shell, except for under the armpits. Unlike his progeny, who are all ravenous monsters who die if they don't feed for 36 hours, he is smart and calculating.
 * In Dracula 2000, he's not only the first, but he's also.

Anime

 * Lucy from Elfen Lied is
 * from Vampire Knight may not be the original progenitor of the race, but he was one of the original purebloods, exerted a huge influence during his lifetime, and founded the royal line of purebloods who kept track of the species. Plus, he's totally badass
 * is the progenitor of all demons—including the five members of the Godhand whose job it is to create new Apostles—in Berserk.
 * In Mahou Sensei Negima, it is implied that Evangeline may be one of these. She's been around for centuries, has none of the classic weaknesses of vampires, was not bitten by another vampire, but transformed, is capable of transforming people into her type of vampire, and has been identified as being of a specific race of vampire.

Comic Book

 * Hellblazer had the King of The Vampires, who was the first vampire and the one from whom all others descend.
 * In the Wolverine Story Arc "Old Man Logan" Bruce Banner is the progenitor of the Hulk Gang.
 * The Marvel Universe has quite a few of these: Varnae is the first vampire, created by dark magic; various demons like Chthon and Set are the progenitors of monstrous races like the N'Garai and the Serpent Men; and the demonic villainess Lilith, who resembles her folkloric namesake in having a legion of supernaturally-powerful children called the Lillin.

Film

 * In The Librarian: The Curse of the Judas Chalice, Judas was the first vampire, but Dracula is not him. In fact, Dracula was.
 * In Underworld, William Corvinus is the Progenitor of all Lycans. Markus Corvinus, his brother, is the progenitor of all Vampires. Unlike other Lycans, William cannot change back to a human. Markus, was unremarkable until he was accidentally turned into a hybrid.
 * Alexander Corvinus is the progenitor of all immortals, but he chooses to live like a normal human and displays no power outside of immortality, which gets him chewed out by Selene.
 * Drinking his blood does give enhanced strength, endurance,.
 * Unlike other Lycans, William is an albino and has the most wolfish appearance. He can also spread the Lycan virus with his claws. This strain of the virus is so potent it can even turn the dead.
 * At the end of Gojira, one of the main heroes suspects that Godzilla may be just the first of his kind. Cue the sequel, Godzilla Raids Again, and it's revealed that he's right as another Godzilla shows up.
 * The film The Howling 2 features the queen and original werewolf Stirba.
 * In The Faculty is the alien queen. Killing the queen kills all of her alien offspring, freeing the hosts.
 * In Slither the alien that takes over Grant Grant acts as this, creating himself a "brood queen" which spawns the parasites that give the movie its title. These infect people, turning them into ravenous zombies. Some of them seek to merge with Grant, while others produce more parasites. Killing Grant ends the infection.
 * In Dagon it is revealed that  are either children or followers of Dagon.
 * It's implied in Lair of the White Worm that the eponymous worm spawned a race of snake-like vampires. It's also possible that the film's antagonist was one of the first or possibly the first.
 * In John Carpenter's Vampires, Valek is the first vampire, accidentally created during a botched exorcism. He is the strongest, as the only thing that can hurt him is sunlight. He lacks every other vampire weakness. His goal in the movie is to complete the exorcism in order to become truly immortal. This would also allow him to make other vampires without weaknesses.
 * In Dracula 2000, the titular vampire turns out to be and progenitor to all vampires. He is nearly impossible to kill (the only way is to ) and is able to turn any other vampire back into a human.

Literature

 * In Glen Cook's The Black Company series, The Dominator is original creator of the northern empire, and the one who Took all of the Ten Who Were Taken.
 * The creature under Old Father Tree is the cause of the uncounted number of strange creatures on the Plain of Fear, or at least the change storms that caused them. HE also refers to the menhirs as his people.
 * In Anne Rice's The Vampire Chronicles, Akasha is the first Vampire, and the progenitor of all of them. She became a vampire when a demon entered her body and fused with her flesh.
 * She is the strongest, especially after draining her husband and second vampire Enkil. She can fly, hypnotize hundreds of humans at a time, incinerate almost any vampire she sees, and track any of her progeny, which she uses to kill off the majority of the world's vampires.
 * Additionally, any damage she sustains is mirrored by all other vampires to varying degrees. For example, when a vampire set her living statue out into the sun, many older vampires had their flesh seared, while the younger ones simply burst into flames. When Akasha is finally killed by decapitation, every vampire falls on the floor, feeling as if their heads were being removed. By eating Akasha's heart and brain, Mekare (the fourth vampire) becomes the host of the spirit Amel and the new queen.
 * The Biblical murderer Cain is a Monster Progenitor by implication in the epic poem Beowulf, as both Grendel and his mother are said to be his descendants. Grendel's mother is a more direct example in the same work.
 * Ugoliant, progenitor of the giant spiders in The Hobbit and The Lord of the Rings's Shelob, from The Silmarillion.
 * The Mother of All Darkness from the Anita Blake series is the ancient progenitor of vampires and possibly werecreatures. Given the series has featured pre-cromagnon vampires, that makes her pretty old.
 * Yaksha in The Last Vampire. Was once a stillborn infant in 3000 BC, but Demonic Possession revived him as the first vampire.
 * In The Dresden Files, The Red King is the Red Court Vampire from whom all other Red Court Vampires came..
 * According to Paradise Lost, while many of the demons are actual examples of Fallen Angels, others are the spawn of Lucifer/Satan and his daughter Sin, making them Monster Progenitors.

Live Action Television

 * Supernatural's season 6 involves the Winchesters tracking down Monster Progenitors, also referred to as Alphas. Alphas do not typically have the weaknesses of their children, and may share some telepathic connections to them. The respective Alphas are in turn topped by their progenitor Eve, the Mother of All Monsters.
 * The premise of Werewolf was a man hunting down the werewolf who bit him to kill him and end his curse.

Mythology And Religion

 * Proving that this trope is Older Than Dirt, Tiamat, the goddess of chaos and salt water in Mesopotamian Mythology, got revenge for the murder of her husband by spawning hundreds of monsters to kill everything in sight.
 * Echidna in Classical Mythology is also called the Mother of All Monsters, and for good reason; her children include Cerberus, Orthrus, the Lernaean Hydra, the Chimera, and according to some authors even the Sphinx.
 * Loki in Norse Mythology is the father or mother of several of the monstrous creatures in the setting.

Tabletop Games

 * As opposed to Dracula, Vampire: The Masquerade pegs Cain(e) as the First Vampire, cursed by God for his slaying of Abel. His line was then split down into three childer (destroyed before the Flood), and thirteen childer unto them, whose ranks and divisions make up the thirteen clans of vampires who exist in the modern nights.
 * Each Promethean Lineage (think Frankenstein's Monster) has at least one Progenitor, created by a human demiurge. Each Progenitor can create more of their kind by using human corpses in a ritual specific to the Lineage.
 * In the Ravenloft boxed set Castles Forlorn, it's suggested that Tristan apBlanc may be this trope for the race of living monstrous humanoids called "vampyres", by way of his half-human daughter. Elsewhere in the Core, Doctor Heinfroth is the progenitor of the cerebral vampire strain of undead.

Video Games

 * The Emperor Ing in Metroid Prime 2: Echoes. Scan logs will tell you that it "is the strongest Ing in the horde, the alpha and the omega," and that "like its bretheren, the Emperor Ing is a metamorph."
 * Raziels vampiric brethren in Legacy of Kain: Soul Reaver all create fledgling vampires that share certain traits with their progenitors.
 * In the Nasuverse, Crimson Moon can be considered the progenitor of True Ancestors and through them, of all vampires. While he didn't exactly spawn them, Gaia used him as a template for her purported defenders against humanity, which didn't go well, since all of them inherited Crimson Moon's Blood Lust, as well.
 * The Dragon Age setting had the Tevinter Magisters who entered and subsequently corrupted the Golden City of The Maker. This, in turn, has corrupted them into the first Darkspawn, who then spread this corruption as a Mystical Plague to start the First Blight. At least one of these Magisters, Corypheus, is still alive and more or less sane a thousand years later, as evidenced by the Dragon Age II DLC.
 * In Mass Effect, krogan legend states that Kalros is this to the Thresher Maw species. Probably an exaggeration, but Kalros is by far the largest and most dangerous Thresher Maw in existence. "When the krogan bother to name something, you know it's something scary."
 * In Monster Girl Quest Paradox, Alice I is the Anthropomorphic Personification of darkness and the first monster. She created the Six Ancestors by using her dark energy to mutate the genes of animals. Each of the Six Ancestors then gave rise to a lineage of monsters: succubi (Minagi), slimes (Kanade), plants (Kanon), beasts and kitsune (Tamamo-no-Mae), scyllas (Hiruko) and harpies and lamias (Saja).
 * The Lich King from World of Warcraft. Not only did he create and/or inspire most other lich villains, but most death knights as well. He's their King, after all.

Web Original

 * Salem from RWBY appears to be this for the monstrous Grimm.
 * The SCP Foundation has several malevolent and dangerous SCPs that are the result of evil deeds committed by the most powerful and most dangerous SCPs:
 * Sarkicism, or the Church of the Red Harvest, is a Religion of Evil that worships decay and disease while creating atrocities via Blood Magic. Its most notable creation is SCP-610 ("Flesh that Hates"), a highly contagious disease that mutates victims into mindless monstrosities. It is also behind SCP-2191 (one of the cult’s founders, a vampiric Hive Queen controlling many similar predators), SCP-2408 (another of its founders, having become a massive subterranean monster), and SCP-2480 (formerly Simon Oswalt, a former SCP beaurocrat who turned against them and became a leader of the cult, able to control its other evil creations).
 * The Scarlet King is believed to be the father of SCP-682, the infamous "Hard-To-Kill Lizard" that has become the mascot of the series. Not all of its children are evil, however. They include SCP-166, who is only dangerous because she has no control over her power, and SCP-999, who is not dangerous at all and friendly to everyone. SCP-999 may even be an Anti-Anti-Christ who will one day strike its father down.
 * It has been theorized that SCP-053 is also an offspring of the Scarlet King. She is not evil, either, but very dangerous - anyone who touches her or remains in her presence longer than 10 minutes is filled with murderous rage towards her. This may explain why SCP-682 would not attack her, or why she seemed so friendly towards it - they might have recognized each other as siblings.
 * Dr. Wondertainment is a toymaker (though it's not clear whether the name is a company or the CEO of the company) who has created several SPCs, including potentially dangerous toys and candy as well as the sixteen "Little Misters" - artificial humanoids with odd anomalous features and/or abilities that range from harmless, to tragic, to dangerous.

Western Animation
Kids Next Door had an episode where Numbah 5's teacher, Miss Thomson, was the queen were-dog responsible for turning her student into were-dogs, including Numbah 5's rival - who ate her homework as a were-poodle in a previous episode. Unlike the other were-dogs, the queen were-dog was able to eat Numbah 4's awful homework without becoming sick.
 * Futurama features the original Were-car, Project Satan, who is the origin of the curse of all Were-cars.
 * In Codename: Kids Next Door,