|Motive||To stop Mystery Incorporated from setting him and his men free, since he wants to pay for his past deeds.|
|Powers and Abilities||Teleporting|
|First appearance||SDMI: Nightmare in Red|
|Played by||Frank Welker|
The Monstrous Freak was the disguise of the spirit of El Aguirre.
He is pale looking and has a freightening skull-like face with long black dreadlocks. He is muscular, only wearing a loin cloth.
He is vicious and terrifying, snarling and showing his fangs.
Powers and abilities
- Teleportation - as a supernatural entity, he can appear and disappear in a mass of swirling black lines. This takes time, so an agile person like Velma Dinkley can leap through him while he is taking form.
Scooby-Doo! Mystery Incorporated
He used the disguise to keep Mystery Incorporated in the sitting room so they wouldn't destroy the evil entity that is in the crystal sarcophagus, because it would set him and his men free; he wants to stay there so they can pay for past evil deeds. He was found to be vulnerable to the light coming from the statues of the Hunters of Secrets. (Nightmare in Red)