Itchy

Itchy (born 1919) is the mouse in The Itchy and Scratchy Show who hurts and/or kills Scratchy in nearly every cartoon, he is voiced by Dan Castellaneta

(There is however one known episode where Scratchy wins and Itchy is killed never to be shown again)

Born: 1919 (age 93) (killed once)

Goal: To kill Scratchy

Allies: none

Enemies: Scratchy, Mrs Scratchy, Adolf Hitler

Fate: Ends up killing or hurting Scratchy (mostly)