Gilman the blowfish

"Gilman the Blowfish has come up for air, and with his natural ability to deal with all water hazards, you’ll wish you could throw him back! He’s set to 'finish destroying all the buildings in your city, and he won’t even feel any 'gilt about it!"

- Official Rampage: Total Destruction

Background
Crock who drank Scum Soda, and it made turn him into a giant blow-fish.