Snake-Eyes

Snake-Eyes is a human member of G.I. Joe in the Generation 1 continuity family.

Snake-Eyes is a ninja. As such, he has been known to flip out and kill people. He is also a mammal. It is rumored he plays guitar in his free time. He doesn't talk much and it's not clear what his face looks like under his mask, but at least one woman thinks he's pretty darn cool.

Statistically, all ninjas are turtles.

Fiction

Devil's Due G.I. Joe vs. the Transformers continuity

Originally, Snake-Eyes enjoyed a reputation among his military comrades for being incredibly talkative; however, due to injuries he sustained when Cobra attacked Washington, D.C. using mind-controlled Decepticons as war machines, he lost his ability to speak and his face was severely disfigured. He subsequently became a founding member of the G.I. Joe team.

From Teletraan I: The Transformers Wiki, a Wikia wiki.