Probably the most thorough dedication to the jam's theme I've seen so far. I'm a sucker for action games that force you to manage everything at once, and this is a really good example of that.
I've played a lot of wave-based arena shooters for this jam (heck, MY game is a wave-based arena shooter), but this one probably has my favorite use of the mechanics on offer. Randomizing your weapon, AND the gravity, AND which enemy is which is a really, really cool idea, that I think gets a lot of mileage despite the game's simplicity. Also a really big fan of some of the small touches in this one, especially how the health pickups are shoot-able, which really forces you to keep track of what thing is what.
Didn't see many bugs outside of the somewhat strange movement/jump (which I've seen that some others have already mentioned), and that the bullet collision can be a little chunky when enemies are close together (there was a moment where a health pickup was stacked on top of an enemy, and both were destroyed in a single shot).
This game is really high on my list of games that I really want to see a polished-up version of. With better graphics/sound, and more things to keep track of (maybe make the platforms shift, or add more enemies), this could be extremely addictive. Good stuff all around.
My entry's below if you want to give it a try. Hope to see you in another jam! I'll be keeping an eye on this entry in particular.