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.
A new map titled ZPO_Corpsington for Zombie Panic: Source
In real life somebody would be crapping his pants now.