Wonderful game, eventually too easy
Despite its namesake, this game really could use an end point. It is wonderful fun for quite awhile, but once you can afford the Laser Canon and the Overkill Powerup, you can easily earn 80,000 experience a round. That is really unfair to the zombies, they go from attacking a dude with a gun, to battling Captain Imortal and his Invincible Fortress.
Also, as impressive as the blood and gore is, it would be nice if the previous session's splatter would slowly fade away during the current slaughter - that way it doesn't get too hard to see the monsters (as it does right now). An indicator that the fortress is being attacked might be nice too. Perhaps having the fortress health blink red, this might allow for a bigger playing field - have our hero have to finish simple tasks, like "defend our water tank from the zombies", when the health bar blinks you know you have to go defend your fortress again. Just some ideas for a more expansive game - but still, this was very slick, very fun, and no doubt it is a top notch submission - keep up the great work!