Forward Smash explodes, Whirling Fortress freezes (I think), Bowser Bomb or maybe that and downward smash creates earthquakes, and fire breath is like, on fire. You know what I mean.
Hmmmmmmm... Pichu's Final Smash should just turn him into Pikachu for a short time. The rawest of deals, right there. That, or an uber powerful insta-death attack. It can't be anywhere in between.