My hard decision was between carnophage and kird ape.
Carnophage:
THE basic 1cc suicide black creature. I remember my suicide black deck. *sigh*
Kird ape:
The best creature in a friend of mine's deck w/ Fling. taiga, Kird ape. forest, Rancor kird ape, briar chield kird ape, attack for 5. Mountain, briar shield kird ape. Attck for 6, cast llanowar elf. Next turn, attack someone else, sac both briar shields, giant growth, berserk. Fling at a third player. That's 46 damage.
However, mothers rule, I guess. They're just so damn hard to kill.