4 minutes and 18 seconds, woo!
Really fun game, and a cool idea. I love the roll to reload mechanic and the upgrades. I didn't know if the explosions were a power up or damage at first. I think it goes from pleasantly challenging to really hard very quickly.
Maybe slow down the enemy generation? Often I would roll a one or two and then just have to wade through a load of enemies and lose so much health just to hit the dice again. After a while I just started avoiding enemies and not shooting.