Fatz Geronimo is a gorilla piano player from New Orleans, Louisiana in The Rock-afire Explosion.
He originated as an originated as an extremely similar character, Fats Gorilla
in a previous Creative Engineering show, The Wolf Pack 5.
His voice was provided by Burt "Sal" Wilson from 1980, until his death in December 2023.
The character was also voiced by Aaron Fechter from 2006 to 2020.
