Fun concept! I liked the idea of chaining together bullets in a risk/reward type of set up. The art looked great and the score counter in the middle of the floor was cool.
If you wanted to improve, I suggest adding some sort of score multiplier to the bullets or increase their power some and introduce way harder enemies. The system is supper fun and adding some form of positive reinforcement for using the mechanic would be amazing!
Overall, good work! Check out my game if you get a chance!