Interesting concept! I like the style and it's quite fun to play.
Just have a few things/ideas. I feel like a bit more ammo and a bit more difference between the weapons (bigger blast radius for the shotgun, collaterals for the sniper) would make the game even more fun. I'm also not sure if the "cards" (?) have any function or just decoration. They look like they should do something. :D
Overall pretty cool game. Goob job!