Say Riot were to make a LoL fighting game. Which other franchise would you borrow mechanics from?

I know there's that whole "League of Fighters" fan-game being made, but that one, frankly, is doubtful to get too far. Now, humor me for a moment and pretend Riot themselves made a LoL-fighter.

If they were to borrow mechanics from another fighting franchise, which would you pick? Street Fighter? Mortal Kombat? Guilty Gear?

I'd personally go with Blazblue. Stylized attacks, anime-style art, 2D fighting, and flashy finishers. Not to mention it isn't as stomach-turning as MKX. Plenty of opportunity for comedy and "tasteful" bounciness. XD

As for playable characters (try to pick up to 15):