From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Gozu (ゴズ, Gozu; FUNimation "Goz"; Literally meaning "Ox-Head") is a large Ogre.
Gozu's skin was blue he had purple hair and one horn. He stopped Son Goku from eating Ensenji by hitting him with a spiked club. Gozu then challenged him to a wrestling match and toyed with him for some time, pretending to help him leave Hell as with Goz's Flying Machine.
Dragon Ball Z
Gozu and Mezu reappeared in "Warriors of the Dead" where they were shown to be in hiding from Cell and his fellow villain rioters. It was also implied in this scene that they would have told Cell and his rioters how to escape from Hell had they caught them in order to save their own lives since they mentioned that they would tell them where the secret lair was when they thought Goku and Pikkon were with Cell and his rebels.
They later reappeared watching the fight between Kid Boo and Goku (and were also impressed by Kid Boo's putting up a fight).
Gozu speaks by adding おに (oni) to the end of each sentence in the Japanese dub.
- Jose Luis Castañeda provides the voice of Goz in the Latin American dub except in the chapter "Warriors of the Dead" when Cell, King Cold, Freeza, and the Ginyu Force wreak havoc in Hell. This is probably because Castañeda also voices Cold and Butta and both characters appeared in that same episode. That would make him the third character in the same scene, therefore the change may have been intentional.