It switches between a 2D and 3D plane
If you're looking for something different, check out this video for the indie Kickstarter Violent Serenity: Battle for Discord. Long story short, it's a fighting game that involves both 2D and 3D camera angles, which switch when you've "edged yourself far away enough towards the edge of the screen."
All of this is in "very rough, proof of concept" territory, but the idea is fairly intriguing. I don't know how serious a fighting game can get with an engine like that, but I'd easily give it a shot.
Violent Serenity [Kickstarter]