Revenge, Inc.

Revenge, Inc. is a group of five villains who banded together for revenge against Mystery Inc..

Scooby-Doo! (DC Comics)
They used a hypnotic gun to trap the gang in their worst nightmares. (Revenge, Inc.)

Appearances

 * Scooby-Doo! (DC Comics)
 * #21(b). Revenge, Inc.