This game is pretty amazing. I bought it on release and I still play it 3 years later. The perk system gives a sense of progression. The enemy types are varied and fun to fight against. The community isn't half bad. It's got charm. Overall it's a solid coop notzombie shooting game.
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Compren esto y maten zombis con sus compadres. Es mejor que el l4d XD

I came into this expecting a dumb doom clone. I was partly wrong, this is a very smart doom clone. It has a neat upgrade system, beautiful ways to blow things up using your surroundings and is all around fun. If you're a fan of arcadey shooters, buy it.

This game is bloody awesome. It's funny, it's clever and it has an incredibly versatile spell system that allows you to create some ridiculous spells and use them however you like. Plus the multiplayer is damn good fun, especially when someone screws up (this will happen. A LOT). This is the best game.