This was fun! I like the increase of the number of enemies showing up over time, it felt balanced. They also spawn quite nicely.
- I wasn't sure how the points tally is meant to work. It's not per kill from what I can tell, so it'd be cool to have it mentioned somewhere.
- Before the first boss, when there are the purple rings that spew out larger enemies: I like the enemy type, but it felt that rather than having to deal with it, I could just drive a bit away and it wouldn't bother me any more. Potentially limit the play area?
Nice work though! Will definitely play any new versions.