It's Kung Fu on the NES with a pinch of more depth. You now have this pretty nice backflip kick (up+kick and then up+kick again in rapid succession) that can trivialize some of the bosses, there's some very light platforming elements and items to pick up such as a bomb. Hilariously, the final boss can be mindfucked in the same way as Mr.X from the NES original by crouching and just kicking repeatedly. Dude walks right into it like a bug into a bug zapper.