Zombie Panic! Source is a standalone cooperative, survival-horror, first-person-shooter! Set in the middle of a zombie apocalypse, players start as a small group of survivors attempting to stay alive. Each map will have its own objectives to complete and win the round or survive by a period of time.
Images of Playtesters playing ZPO_Harvest.
Is that like the house in L4D?
not really but its like it and i think that L4D copied ZPS