the zombies spawn quite fast i eventually lost because of lag also i would be nice if the purple orbs would come to you from farther however its a great idea

The balance seems quite off. There are a ton of zombies, so I had to be on the run the whole time. At first they seemed impossible to kill, but then I unlocked piercing shot, which helped to damage many zombies at once. At the time I though the the game has been won and it's just a matter of grinding to finish the win: running around in circles avoiding zombies and mining green-stuff on the way.

But there were some fast zombies, so despite trying my best, they managed to hit me one by one, and eventually I died at just 9.2%.