very fun! i've won after over an hour total
possibly a bug: i wanted to try playing without the "pierce" passive but when i reset the upgrades, bought every passive but that one and switched to weapon upgrades and upgraded those, the pierce passive also suddenly turned out to be bought and this happened two or three times the same way... though after that i reset and started with buying upgrades and pierce didn't appear against my will. buying a lot of upgrades at once is annoying so i'm not trying this more to figure out if it's actually reproducible...