Multi-eyed squirrel

The Multi-Eyed Squirrel was a pink, mutated, multi-eyed squirrel with 38 eyes positioned 360 degrees around his head (counting the two on his sides which pop out later than the rest) and tannish-white chipmunk-like markings on his head and back and sharp white pointy fangs.

He is mutated at Lake Springfield after Homer dumps an overflowing silo filled with pig excrement into the already heavily polluted lake, causing it to become highly toxic. When chased into the lake by a raccoon, it emerges a mutant. While on a hike together nearby, Bart and Flanders encounter the mutant before it is captured by the EPA and presented to President Schwarzenegger. His many eyes fulfilled part of the prophetic vision Grampa Simpson had.

Toy
The mutant squirrel is seen in the Simpsons Movie figure set "What You Lookin' At?", depicting the scene where he is found by Bart and Ned Flanders during a hike. The squirrel was originally concealed in early pictures of the set, presumably to avoid any leaked plot information, but pictures of the full, unblocked set soon leaked onto the internet before the figure's release.

Altered Opening
He also briefly appears in the altered opening sequence of the first episode of the Simpsons 19th season, "He Loves to Fly and He D'ohs", where he is seen jumping on Bart and being hit by a wrecking ball.