A fun game that fits very well int the theme of running out of power and is among the best games I have seen made for this themed contest.
Gameplay is fun. The unique restriction of your gun having to be plugged in in order to fire isinteresting. Regular enemies are cool and fun.
Obviously the game is too short as most of these rushed contest games are.
Also the boss is not balanced well. A good boss would have a high hp and spawn zombies at reasonable rate to make that battle a long battle of endurance. This boss had low HP and could overpopulate the room with zombies in a short time, which meant that the only way to beat him was to berserk on him, ignoring zombies and even taking his attacks, just to kill him as fast as possible. It's great that he had three different attacks but you had to ignore all that anyway so it's a waste.