Robots vs Zombies

You are going to play Robots vs Zombies for few days or you just forget about it. The content is quite fine. The style is classic Tower Defense fun where you try to stop hordes of zombies and guard special objects. You own a powerful robot which can be improved like the towers in the game. The zombies are various, the upgrades are various, and skills are various. So what's the problem? The game is extremely over combined. Some gamers will like it but ordinary people will be often lost.