The listing, Zombie Playground [steam key] has ended.
http://store.steampowered.com/app/215550/
+2 dlc, 1 free in steam.
Zombie Playground™ is Goonies meets Attack the Block meets The Walking Dead. The mood we want to capture in Zombie Playground is the feeling that you had as a child when you were completely immersed in your imagination fighting monsters and doing things you thought were cool from your favorite movies, comics, and video games.
Stealth Studios Inc. has worked long and hard to create a game that delivers on the promise of our original vision. Zombie Playground™ is made with the brains, disease, and puke of all involved - that means heart! We've put everything we have into this development, and we intend to put a lot more.
Gameplay in Zombie Playground is a hybrid of third person shooter and action RPG mechanics set in a cooperative zombie survival horror arena. This translates simply to "A fun romp solo or with friends."