This was really fun, great job mate!

Things I loved:

• Really addictive roguelike loop, ended up playing for half an hour! :D
• The shooting was hella fun, I liked the tactical crunchiness of lining up shots and managing your overheat while trying to figure out which clusters were most worth going for
• Very comprehensive upgrade system with a lot of stats + strategies to consider
• Really nice transitions + banging soundtrack 8)

Things I'd love to see:

• An explainer on the stats somewhere would be good, I was stacking Luck out of a roguelike habit but wasn't actually sure what it was applying to! :P
• I could buy both nuke + freeze but only one would actually apply to the run, so it'd be good to either make it possible to queue them one after the other OR just disable the other shop option if you've already bought one type so you don't waste money on it
• Sound fx for the UI selection in the menu might be nice

Oh also, did have a weird bug where my Heat progress bar flipped to the left side (outside the border!) after 10 or so runs, which then made it a little hard to progress as I couldn't tell when I would run out, but hey such is jam games and overall great work ^-^

The flamethrower was really fun. I liked trying to line up all my shots to get as many enemies as possible with one spray.