Needs work, sound, a lot of love
You need to fix your sprites: they bounce all over the place. Also, work on your animation. The character don't move fluidly at all. It's very obvious where the tweening is.
Fix the size of your background to match the size of your sprites, or vice versa. Two small sprites on a massive background is no fun for anyone.
Where's the sound? It's very boring to watch two poorly animated sprites do battle with no sound.