Excellent game, I love the artstyle and how the red enemies stand out against the blue background. I found the weapons very interesting (though the flamethrower wasn't as good as the default weapon). My only complaint is that some room layouts just make it impossible to make my way back. I know that this is due to the random level generation, but it lead to a couple frustrating situations.

For example, 2 ammo pickups spawned near the start of the level, so I wanted to grab a weapon and then come back, except no weapons spawned so I went to the weapon shop... but it was impossible to come back to grab the ammo.

Another example is when I got to the shop and bought the map, revealing the secret room... which was above me and there was no way back. I still don't know what the secret rooms look like in this game.

Overall, a great start and I hope to see more of this.