Koala Kong

Kong is a boss/villain in the first game but only has a few more appearances after that in cameos.

Crash Bandicoot
 Cut Animated Intro 

Kong was an ordinary Koala Bear until he was rounded up by Cortex and Brio for experiments, he was evolved by Brio so he is loyal to him, he was a test of trying to give a minion super-strength but it failed to give him any brains to go with his brawn.

Due to his strength but tiny brain Cortex decided he was a waste and made him the worker of his Wumpa Islands Mineshaft.

 Boss 3: Koala Kong 

Cortex finds out that Crash has made it too his Mineshaft and informs Koala Kong to kill him, Kong meets Crash and shows off his muscles before beginning to throw rocks at him and knock TNT Crates down at him, Crash spins the rocks at him knocking Kong into a Minecart that takes him off to Cortex Island where he crashes and falls out of it defeated.

 End Credits 

Koala Kong somehow managed to move to Hollywood where he worked on a movie as well as getting a speech therapist to help him learn how to talk, somehow nobody has figured out that he isn't human.