The variation in enemy types was pretty neat. The first level's enemies got a bit bland though, if they alternated between cardinal and ordinal directions when firing it would have been more interesting. Instead I found myself standing still next to one stream of bullets waiting for an ammo pick up.
Having to pick the bullets to fire them back felt pretty fun. I think it would have greatly added to the mechanic to emphasize each bullet somehow, like a louder SFX for hitting or the enemy flashing white on hit.
The audio was decent. The art was cute, I like the lean, even with no animations it still felt nice to move because of it.
Overall, a cool submission.