That's the name I settled on: Mambo Jumbo. You first meet him in a freezer where you find a gang of villains who are trying to subdue him, but Mambo turns on them, which triggers a sequence where you play as Mambo to fight the badguys, though they aren't pushovers. When he wins, he will shift into a smaller elephant named Mambo Mel and join you.

*Sigh* he doesn't look as good in sprite form.