It took a few plays of this game before I finally started to understand it. I like the concept of a turn-based co-op game where you don't know what the other player's going to do. But this game's design holds it back from itself.
For one, the text-based tutorial goes by very fast; it wasn't until I opened the game for my third time and read it in full that it finally started to click what I needed to do. Also the controls are not fully explained in the tutorial; I only knew how to shoot based on the "press g and n to continue" prompt, and guessed that the arrow keys were my controls. Later I guessed that the WASD keys were player 2's controls, and I was right.
But the poor design goes deeper than that. I'm still not fully sure what the red boxes on screen were; I think that was my health? At first I thought they and the grey boxes on the side were part of the environmental design. It wasn't until I decided to start the game with 2 bullets per player (why does the game automatically have zero bullets per player, btw?) that I realized those boxes was my ammo. It's all very unclear. And the g and n keys aren't the best keys to pair with the arrow keys and WASD keys, respectively.
Also, pressing "play" with my mouse only turned the sound effects on and off. I think you should look into that; I had to use the arrow keys and g key on the menu.
Overall, an interesting concept. But failure of design holds this game back. I'd consider polishing it after the jam; this game could be something great.