Well, since we're sticking with Nintendo characters, I'mma have to go with Ike.
What?
I'll bet 90% of you kids never played Fire Emblem, and can't point out Ike's final smash should be more epic, because he should be attacking twice. Though in all fairness, Fire Emblem isn't that great of a game.
Outside of nintendo characters (but still from Japan), Overlord Zetta from Makai Kingdom for brutal power, or Advocat from GrimGrimoire for sheer awesomeness.
Actually, let's just go wit Advocat.
"Watch yourself, or else I'll do things to you your simple soul has no way of comprehending. Oh, excuse me, that was uncouth. Your soul is not simple, it is, 'rustic.' "