Royce "Cave Guy" Mumphry
Species Human
Gender Male
Confidants Cobra Queen
Rivals Freakazoid
Sergeant Mike Cosgrove
Roddy MacStew
The Huntsman
First appearance "Dance of Doom"
Voiced by Jeff Glen Bennett

Cave Guy is a very intelligent blue caveman with upper-class diction education,and taste. His real name is Royce Mumphry; he is wanted in five states, and he subscribes to The New Yorker. His enemies are Freakazoid, Sergeant. Mike Cosgrove, Roddy MacStew and The Huntsman. In season 2 to he dates Cobra Queen. He also does not like Sci-Fi conventions. He always goes to the Washington Gardens to eat. He also has the strength of 20 men.