old disney movie where villains jump in pot and transform

Taran is an assistant pigkeeper with boyish dreams of becoming a great warrior. However, he has to put the daydreaming aside when his charge, an oracular pig named Hen Wen, is kidnapped by an evil lord known as the Horned King. The villain hopes Hen will show him the way to The Black Cauldron, which has the power to create a giant army of unstoppable soldiers.

On the night before Halloween, the Evil Queen from Snow White and the Seven Dwarfs plans to conquer Halloween, and asks her cauldron to show you several villains, to which one of them helps her in her plan, such as Peg Leg Pete from Mickey & Co., Ursula from The Little Mermaid, Captain Hook from Peter Pan, Yzma from The Emperor's New Groove, Professor Ratigan from The Great Mouse Detective, Alameda Slim from Home on the Range, and Judge Frollo from The Hunchback of Notre Dame The cauldron also explains its origins and The Horned King, both from The Black Cauldron.

Mad scientist Mickey has just brewed up a potion; to test it out, he squirts it on a fly that's been trapped by a spider, a (regular) mouse being harassed by a cat, then the cat when Pluto goes after it, and Pluto when dogcatcher Pegleg Pete goes after him. Each of the underdogs turns against his tormentor.

Mickey's orphans ask for a story; Mickey casts himself as Jack in Jack and the Beanstalk. He starts with the climbing of the beanstalk; after evading the giant a few times, he ends up inside a cheese sandwich, and then in the giant's mouth, where he ultimately grabs onto a pipe and gets pulled out by the giant. In the ensuing chase, Mickey launches a pepper bomb to slow the giant down, then outruns him coming down the beanstalk and sets the stalk on fire.

The insects have completely taken over Mickey's garden. He spritzes them with insecticide, but runs out and they keep feasting. He mixes a new batch. Meanwhile, Pluto stalks a bug and gets his head stick in a pumpkin. He stumbles around and bumps into Mickey and the sprayer, giving Mickey a faceful of bug juice. He awakens to a warped reality, where the bugs and plants are giant sized, and the bugs get drunk on the insecticide and chase our heroes. Mickey recovers from his nightmare, discovering the giant worm he was wrestling was the hose.