The artstyle and player controls are very nice. I have some points for improvement:
1. The enemies are very sticky once they get near the player. If I try to jump over them they immediately jump too and stop me and it feels a little frustrating.
2. The gears the enemies drop refill both ammo and HP. For more depth, maybe separate it to one item for ammo and another for HP?
3. The sounds are a little repetitive which gets annoying pretty fast.
For its scope, not a bad game at all. Just needs some polish.