An “extremely early” Left 4 Dead prototype is now available to play thanks to Counter-Strike’s 1.6 update.
According to content creator Gabe Follower, the prototype – called Terror Strike – was “accidentally compiled” and added to the Counter-Strike update, showing how the zombie game’s DNA lies firmly in the mod for Counter-Strike: Condition Zero and was developed using CS assets, including Counter-Strike weapons.
The files were quickly pulled from the 22nd November update, but not quickly enough to stop them being yoinked and then distributed publicly.