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CatRoots is a cancelled Nintendo 64 game. Other than brief footage from E3 2000, not much at all seems to be documented about it online.
The game, drawing inspiration from works like Tom and Jerry, and The Simpsons' The Itchy & Scratchy Show features a red cat, who is chased by an aggressive blue mouse who tries to attack it with weapons. As a Game Over message was shown after the mouse defeated the cat, it is possible the player assumed the role of the cat.
CatRoots was cancelled due to its graphics being "too sharp and smooth" for a Nintendo 64 game, according to N64 Magazine via IGN.