The 13 Ghosts of Scooby-Doo (1985)

S1E1 To All the Ghouls I've Loved Before

The gang touches down in a town inhabited by werewolves, where Bogel and Weerd deceive Scooby and Shaggy into unlocking a chest filled with demons. Meanwhile, they encounter a small-time con artist named Flim-Flam, who decides to team up with them.