Cool game, solid mechanics. I think due to a lack of progression in difficulty, enemy variety, or bullet variety, it started to feel a bit repetitive after a few waves. It was also too easy. I had five lives when I got to wave 8 and quit playing because I felt like I would just end up doing the same thing for an hour otherwise.
Viewing post in Hexatron jam comments
By wave 10, the difficulty should be high enough to see the merge mechanic and another enemy type. I didn't have that much time at the end to play test and balance unfortunately. otherwise I would have that introduced sooner. Maybe you already saw those, but it adds a tiny bit of variety.
Thanks for the feedback! Bullet variety would would be really neat to add after the jam too.