This can be any character from any wii game ever. The last time I did this, it was ruined by Xbots. So I narrowed it down to the wii.
I think Samus takes the cake. She must've killed at least a million space pirates, and even more casualties to nature itself. If she passes by harmless parsites she will own them. when I played nes metroid, (it was before metroid prime came out or when I didn't even know what Samus was) Samus was so tough I thought she was a man until the end. She totally beats Mario. Anyone disagree?
p.s. I can't believe there is no Samus smiley.