Its called State of Decay. Its nothing like the walking dead, no where near the amount of emotion in it, its actually pretty comical in a way. But what you can do in the game is pretty amazing. Its open world, kind of like GTA ( no where near as detailed though ), %90 of the houses and bulldings are enterable and contain supplies, you have to be careful when you search because the zombies will hear you. You can choose to get round by car but it makes noise.
There are 4 option when it comes to choosing a home base, each one is better than the last but requires more people to help keep it ion good shape, in the base you can build things like workshops to repair your damaged wepons and make silencers and stuff, a medical area to help with the injuries, a garden for when the food in the 2 towns runs out, a sniper tower, you cans et up an outpost's as a place to rest and restock while out on runs
It has many good aspects and also many bad, frustrating ones but its a whole bunch of fun!