Merlock is an anthropomorphic dog. He possesses a green magic talisman that gives him magic powers, which include the ability to transform 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 a city but a luxury resort - and Merlock couldn't get a reservation, so he wished it, causing Dark Cynder to destroy it.), the eruption of Mount Vesuvius that wiped out Pompeii, and the creation of anchovy pizza.
In DuckTales the Movie: Treasure of the Lost Lamp, 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. Dijon is later hired as a guide to Scrooge McDuck, who is searching for the treasure. The lamp ends up in the hands of Webby Vanderquack. When Dijon fails to steal the lamp, Merlock becomes angry and attempts to trap the group. Luckily, Scrooge and the others are able to escape.
Near the end of the film, Merlock is able to take the lamp for himself, and forces the Genie to grant his wishes. Merlock has the Genie turn Scrooge's money bin into a recreation of his old floating fortress, and later tries to have Scrooge destroyed. Scrooge is able to take Merlock with him, and engages in an aerial battle with the sorcerer. Eventually, Scrooge is able to regain the lamp and turn everything back to normal. Merlock loses his talisman during the flight, resulting in the loss of his powers. Merlock is last seen falling to his death.
Role in the series
In the spongebob series, Merlock will reprise his movie role, but also have a dark secret he's been keeping. As it turns out, he killed Shenzi's parents, to provide souls for Malefor to control, and to seek revenge on what Malefor thought was the last of the prue-breed Hyenas, and to cause the normal breeds to turn to pitiful rouges without proper guidence, and he did this in his mountain lion form, which is why Shenzi became easy prey for Scar to command in exchange for the demise of the Pride Rock monarchy. He'll team up with Dr. Facilier and Jafar, and their Side-kicks Abis mal and Lawence (human), as the ofittal villains, cause that female villain stuff was fan-made stuff from an over-too-eger fan.