Aaahh!!! Real Monsters (1994)

S3E17 Fistful of Toenails

Ickis, Krumm, and Oblina stumble upon an ancient film while rummaging through the dump, and they become obsessed with watching it, much to the Gromble's annoyance. Inspired by the movie's characters, they start mimicking their actions and even attempt some risky cowboy stunts while trying to scare others.