The Monster attacked Jump City in the episode "Dude Relax". After putting a shock collar around Robin's neck to force him to take a day off, Starfire, Raven, and Cyborg confronted and battled it in the heart of the city. Unfortunately, they got wrapped up in its tentacles. They frantically called Robin for back-up, but he chose not to answer so he could take the day off. Beast Boy did not help either because he replaced himself with a random animal he painted green so he could also take the day off.
The Giant Mutant Octopus is a giant octopus-like creature with a red-purple scaly body, fins, tentacles, sharp teeth and one giant eye.
- Dude Relax (debut)
- Some of Their Parts (cameo)
- The Giant Mutant Octopus is the first villain to successfully defeat or capture the Teen Titans.
- He appeared on a few promotional pictures of Teen Titans Go!.