Steve is a big, slimy turquoise monster from the episode Super Zeroes. He is voiced by Dee Bradley Baker.
He explains to the girls that he's upset about their no-shows (because they thought they'd be better with flashy costumes and different transportations) and didn't even fight him right on the third day he came to destroy the city. He lives on Monster Island, where if a monster that attacks Townsville (subsequently fighting the Powerpuff Girls) and returns alive is proclaimed a hero. In the end, he tells them that they don't need flashy costumes and different transportation etc, cause they still have the bravery and courage to save the day. The girls realize he's right and beat him up in their usual fashion.
- Steve also served as the host of a programming block that aired on Cartoon Network Asia in 2001/2002 as part of a special event.
- Steve's design and eye-beams are almost certainly a reference to the Toho monster, Hedorah.