Pythagoras Buck was a Weasel in the mind of another weasel named Buck.
Pythagoras Buck and his friends, Neil deBuck Weasel and Robo Buck were characters in Buck's mind that helped Crash and Eddie understand how the space rocks would help them save the world. A few days later, when Buck was captured by a a group of dino-birds, once they revealed their plan on surviving the asteroid, in Buck's head, Neil deBuck Weasel admitted that the plan had majored flaws, with Pythagoras Buck shaking his head in disbelief. After the asteroid was diverted, Buck ended up at Julian and Peaches's wedding, dancing, as his figments danced as well.
- Ice Age: Collision Course (First appearance)