Merlock is an anthropomorphic wolf. He possesses a green magic talisman that gives him magic powers, which include the ability to turn into (non anthropomorphic) animals, including a hawk, a beetle, a gryphon, a bear, and a mountain lion. When placed on the Genie's magic lamp, the talisman grants Merlock an unlimited number of wishes to be granted, instead of the usual three.
At some point in the past, Merlock was the Genie's master, and was granted immortality as his first wish. When he had possessed the lamp, some of the sorcerer's wishes that were unwillingly granted by the Genie included his own immortality, the destruction of Atlantis (which, in this case, was not just a city but also a famous vacation resort - and Merlock couldn't get a reservation), the eruption of Mount Vesuvius that wiped out Pompeii, and the creation of anchovy pizza.
In the movie, Merlock (a portmanteau of Merlin and warlock) is obsessed with retrieving the genie's lamp, which he apparently lost to the thief Collie Baba (a parody of Ali Baba) centuries before. Collie Baba buried the lamp, along with a large amount of treasure, in the middle of a desert. To this end, he hired Dijon to steal the lamp and act as a guide to Scrooge McDuck, who is searching for that very treasure. Merlock attempts to use Scrooge's ambition to obtain the lamp for himself. After Scrooge finds Collie Baba's treasure, Merlock steals everything in hopes the lamp was there, while leaving Scrooge, his nephews, Launchpad, and Webby to die, unaware that Scrooge personally gave the lamp to Webby, as he thought it was a worthless oil lamp, while Webby thought it was a teapot.
When he learns that the lamp isn't in the treasure, Merlock deduces that Scrooge still has it. Also, when he came back to the room where he sealed Scrooge in, only to find the duck gone, he concludes that he wished himself and his family back home. A few days later, Merlock comes to Duckburg, trying to steal the lamp back at Scrooge's home, taking on the form of a rat to sneak in, but due to the chaos caused by Huey, Dewey, Louie and Webby with their wishes with the genie, Merlock was chased by a stuffed tiger doll and then got an undignified thrashing from Mrs. Beakley's broom.
Shortly after that, when Scrooge finds out the boys' new "friend" is a genie, he instantly wishes for the treasure of Collie Baba, and takes a helicopter to a lodge party to announce his discovery of the treasure. Merlock changes into hawk after him, with Dijon in his talons. While the two trying to find Scrooge and genie at the lodge, Genie spots Merlock and manages to help Scrooge to avoid confrontation with the wizard. However, Dijon managed to find the lamp while Scrooge ends up taking a gravy boat. Rather not to be handed over back to Merlock, genie gets Dijon to make wishes for himself, since he is the lesser of two evils. Dijon's first wish: Scrooge's fortune, a wish that led Scoorge in jail, where Merlock, as a cockroach, followed the ex-millionaire and his family as they break into the Money Bin in order to get the lamp back.
Like his time as a rat in Scrooge's home, Merlock faces a lot of painful encounters through the traps in the Money Bin, but it paid off as he crawls up to Dijon's hand, taking the lamp for himself. And with his talisman on the lamp, he literally can have anything he wants. His first wish is having Dijon turn into a "swine," then wishes for Scrooge's Money Bin to turn into a recreation of his old floating fortress, a dark thorny rock castle. His next wish is to have Scrooge be blown out of the castle and fall to his death. It is then that boys and Webby attack and make Merlock drop the lamp over the side of the castle. He then turns into a griffin and chases after it. Both he and Scrooge fight in midair, but since Merlock is holding his talisman, Scrooge knocks it out of his hand, transforming himself into his normal form. Merlock then plummets through the clouds, most likely falling to his death.
Legend of Illusion
Merlock's next appearance was in the video game Legend of Illusion starring Mickey Mouse, in which he is known as the Sorcerer of Darkness and is responsible for stopping the River of Time and threatening the Tree of Life in the process. Mickey Mouse must defeat Merlock in order to restore everything to what it once was. He mainly uses fire and lightning to attack. Eventually, he'll change into a dragon, changing his strategy entirely. He will breath fire at Mickey, fly to the other side of the screen, and toss a spiked ball in front of him.
Donald Duck: Goin' Quackers
Merlock also appears in the video game Donald Duck: Goin' Quackers! as the main antagonist (whether this indicates he survived the events of the film is unknown). He captures reporter Daisy Duck after she infiltrates his temple, and Donald Duck sets out to rescue her. In the final level movie, Donald Duck reaches Merlock's lair, and the final battle between him and Merlock begins. Merlock has three attacks. The first one is to make the floor tiles disappear. Second, to unleash arrows, and the third is the fire attack. In the end, Donald rescues Daisy.
Merlock is shown on the cover of an issue of BOOM! Comics take of DuckTales, along with some of Scrooge's other enemies.
Heroes and Allies: Scrooge McDuck | Huey, Dewey and Louie | Launchpad McQuack | Webby Vanderquack | Betina Beakley | Duckworth | Gyro Gearloose | Doofus Drake | Fenton Crackshell | Donald Duck | Bubba the Cave Duck | Gene the Genie | Glittering Goldie | Admiral Grimmitz | Duchess of Swansylvania
Villains: Beagle Boys (Big Time, Burger, Bouncer, Baggy, Bankjob, Bugle, and Babyface) | Ma Beagle | Flintheart Glomgold | Magica De Spell | Poe De Spell | El Capitan | Merlock the Magician | Dijon | Cinnamon Teal | Dracula Duck
Organizations: Junior Woodchucks