As far as I can tell, the game seems to be glitched, firefox freezes every time I click 'new game' (and it crashed the third time i tried reloading). The game gets boring rather quickly from the lack of variance in enemy types, (i see the normal bots, 'doggy' runners, and Tanks) . I didnt see any indication of weapon upgrades, so i dont know if I had to play longer to get them, or if I had already recieved them but had no notice.
Also, there's no reason this game needs to be rated M, you're just shooting robots with other robots, no one relevant is going to complain about the plot, T would be okay, if not E...