“Zombie_City is a map created by Valve (or possibly Turtle Rock Studios) that was a part of the map sources folder that released today,” WolfCl0ck said about the mod. “It is likely the starting point of Left 4 Dead, and for those of you who have heard the name ‘Terror-Strike’ before, you will love to get the chance to play this prototype level.” To get the map working smoothly, the Zombie City mod gives the original map some nips and tucks to textures and adds a nav mesh. Zombie City tasks Counter-Strike: Source’s terrorists with placing a bomb while fending off an infinitely respawning wave of undead counter-terrorists who can only use melee attacks. As noted by GamesRadar, YouTuber Tyler McVicker claims that the leaked map represents developer Turtle Rock’s original prototyped vision for a multiplayer shooter infested with a zombie horde that got the attention of Valve, leading to the creation of Left 4 Dead. Only a few screenshots from Turtle Rock’s Terror Strike project have been seen before now. Counter-Strike: Source is on Steam for £9/$10/€10.
