GTA: Zombie Situation
You just arrive to your home and found out that your wife is out. You are tired, so you thought of watching TV to be relaxed. But the news that you heard wasn't relaxing at all as zombies have been coming out from nowhere. You get out of your house and found a few of the flesh eating zombies. You grab your gun and unload your fury at the zombies. The idea here is to eliminate all zombies in a level. You would get some money after every level and you can use that to upgrade and existing one or buy another weapon.