Hi. I tried your game out. I have a few comments to make:
1. I think there's an error in your controls. If I tap space bar, I can just fly away.
2. It would be cool if there was an option where movement is mapped on the left hand side of the keyboard (WASD) and attacks on the right side (O,P,K and L). That's how it is on all console controllers...so it might be a good idea to stick to tried and tested control system,
3. The jumps feel floaty but this isn't necessarily a bad thing.
4. Nice visual style. It has that "vector graphics" look. But I think some detailing here and there would help.
5. Music is very distracting.