"This bitch has been stirring up trouble since we started." -Terror MaskTeratoids are large demonic creature with curved horns coming out from both sides of the head, with a long spiked tentacle in place of the right arm. With more than one of these guys in an area it can literally be hell. The Teratoid can wrap its tentacle arm around Rick, squeeze him, and whip him a cross around the room doubling the damage. Teratoids are able to send other creatures into a frenzy, making their attacks stronger than usual. Teratoids can regenerate lost health over time.
Demon Teratoid: Like the Teratoid, but only stronger, has longer horns, and it has a skull appearance to the head. The Demon Teratoid has red markings on its body.
- A Teratoid was responsible for the removal of Rick's left arm during the cutscene in Phase 1: Satan's Masque.
- A glitch exists where the eye-glow effect of a Teratoid's head can be left behind on the environment after its death. It is unknown how this is caused.