Pretty neat shmup boss-rush prototype!
It's got the fundamentals down pretty well as the core act of shooting looks and feels pretty nice, the bosses have some nice varied attack patterns, and there are some neat characters to pick from: it's simple but fun!
It's playing around with some neat ideas too: having your ammo and health tied together in one resource which you replenish by parrying keeps things exciting and strategic, and the roulette system alongside random boss changes is an interesting idea to keep things fresh for every run.
It did have a few things that got in the way of me fully getting into it though:
*The minor statistical upgrades you and the enemy get from the roulette, as well the random cosmetic looks to the bosses, did not do enough to keep things interesting and just felt really superficial and lackluster. I really wish there were more significant changes, like if the roulette would to grant new powers and bullet patterns to the bosses.
*The damage feedback felt really vague and confusing at times: I'd swear that I parried a bullet but instead I got hit?
*Some of the physics of the game just felt kinda wonky, like bullets that should be being reflected back to the enemy would just fly off in weird patterns.
*Some of the bosses like the worms were just very annoying to fight since they constantly dip behind you where you can't hit them, and all you can do is wait for them to emerge in front of you once again.
So yeah, the execution wasn't totally on point for me, but I'd consider it a good game jam result because it's got a good foundation and some neat ideas that I'd like to see expanded upon, so well done in that regard!