Night Monster
The Manhattan Monster is the titular antagonist in An American Tail: The Mystery of the Night Monster. Its a imaginary monster that haunts Fievel's dreams and has been responsible for the disappearance of several mice throughout New York. Throughout the film, the monster takes many forms (among them, a Chinese dragon, a three-headed hydra and a sea serpent), but its true form (at least, as Fievel imagines it) is a red, fiery cat-demon creature with a mouse trap on its tongue. However, at the climax of the film, its revealed that the monster was a machine created by Madame Mousey. Near the end of the film, Fievel faces his fears as he finally knows that the monster is not real. In Fievel's mind, the beast was removed from existence.
           Don Bluth Villains

Animated Features
NIMH | Jenner | Dragon the Cat | The Spider | Warren T. Rat | Digit | Mott Street Maulers | Moe | Sharptooth | Carface Carruthers | Killer | Hellhound | Grand Duke of Owls | Hunch | Grundel Toad | Berkeley Beetle | Mr. Mole | Ms. Fieldmouse | Queen Gnorga | King Llort | Drake | Rasputin | Ludmilla | Drej Queen Susquehana | Drej | Preed | Joseph Korso

Cat R. Waul | T.R. Chula | One-Eye | Mr. Grasping | Toplofty & O'Bloat | Chief McBrusque | Scuttlebutt | Madame Mousey | Twitch | Slug & Bootlick | Manhattan Monster | Red | Belladonna | Martin Brisby | Dr. Valentine | Muriel & Floyd