I was - for once - not even thinking of MLP! I was thinking more along the lines of something in my own campaign world, that I did well before MLP showed on the horizon, where I've chucked the 3.5 bestiary out of the window and re-imagined stuff from mythological sources; there, unicorns were a step up even from D&D unicorns, being basically Shire-horse-shaped paladins with a +3 magic longsword duct taped to thier skulls...! (About as opposite from "little" unicorn ponies as you could get!)
One of the PCs in one of the parties I run is one of those unicorns (a dragon shaman, as it happens), with a ring of jumping. When she uses leap attack, with her jump skill (all those movement-related bonuses), she makes like, 50-60' or something daft and the enemy tends to not so much die, as splash...!