Up to three simultaneous players control the monsters George (a King Kong-like gorilla), Lizzie (a Godzilla-like dinosaur/lizard), or Ralph (a giant werewolf), created from mutated humans. When they were humans, George was a normal middle aged man, Lizzie was a young woman, and Ralph was an elderly man. They were experimented on at Scumlabs. As monsters, they need to raze all buildings in a high-rise city to advance to the next level, eating people and destroying helicopters, tanks, taxis, police cars, boats, and trolleys along the way.
The Atari Lynx version adds a special fourth character named Larry, a giant rat.