Just a generic snake! We looked at hundreds and hundreds of animals and realized, we can't fit them all in the Rulebook! So the Rulebook features many options, and later supplements will feature many more.
Hopefully it's clear how to build your own animals (each gets two powers and sits in one of six categories based on the type of body plan they have).
Please feel free to let us know what animals you'd like to see in future Blister Critters supplements—and thanks so much for supporting the game!