Werecats
If you’re familiar with Zombie Island, though, you’ll know that the real villains of the piece are the Werecats, Simone, Lena and Jacques. The scenes where they transform into the feline forms could genuinely come from a horror film.
Witch’s Ghost
While not as scary as Zombie Island, sequel The Witch’s Ghost has some spooky moments in it – particularly the last 15 minutes, when the evil spirit of Sarah Ravencroft escapes from her book prison. She’s got to be one of the most powerful enemies Scoob has ever encountered.
Scrappy-Doo
Writer James Gunn (Guardians of the Galaxy) has said that he set out to totally destroy Scrappy-Doo’s reputation in 2002’s live-action movie, hence why Scooby’s nephew is revealed to be the film’s secret villain. Well, James, mission accomplished. Scrappy’s hardly returned since.
Professor Pericles
Voiced with sinister aplomb by Udo Kier, Professor Pericles is like Hannibal Lecter if he were a creepy German parrot. Pericles is a perfect foil for Scooby in Mystery Incorporated. And his eventual monstrous, tentacled transformation is nightmare-worthy.
Runners up: the Ghostly Gondolier (The Scooby-Doo Show), the Tar Monster (The Scooby-Doo Show), the Headless Horseman (The Scooby-Doo Show), the Mirror Monster (Scooby-Doo and the Ghoul School) and the Giant Turkey (Scooby-Doo and the Witch’s Ghost).
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