After engaged on Counter-Strike: Situation Zero beneath contract for Valve, Turtle Rock Studios had a few concepts within the works. One was a first-person wizard game that by no means obtained off the bottom, whereas the opposite was a mod for Counter-Strike that reworked the counter-terrorists into bots who got here at you in swarms and solely attacked with knives. This was Terror-Strike, and it was the muse of Left 4 Lifeless.

As Turtle Rock founder Michael Sales space explains within the Left 4 Lifeless commentary, “Whereas we had been creating bots for Counter-Strike: Source we found that a couple of of us armed to the tooth with computerized weaponry in opposition to 30 knife-wielding enemy bots was a number of enjoyable. After delivery Counter-Strike: Source in late 2004 we began experimenting with new game prototypes. That primary kernel of ‘small group of buddies in opposition to hordes of clawing enemies’ was one thing we stored coming again to and we quickly realized that the ‘co-op vs the horde game’ had a ton of potential.”

Whereas issues just like the Particular Contaminated and the personable survivors with their cheery banter got here later, the Terror-Strike prototype demonstrates the essential thought’s feasibility. Shooting hordes of enemies who do not shoot again really is a number of enjoyable. Performing a determined reload whereas backpedaling down a hallway because the unhealthy guys cluster and chase you is a frantic good time.

This prototype is a component of a bigger leak of Counter-Strike map sources. Known as “Zombie_City”, it could be both the unique model of the idea that Turtle Rock confirmed Valve, or a barely later iteration. Modder Wolfcl0ck carried out a couple of tweaks to make it playable. “My add fixes a texture by including a brand new materials for it”, they write. “I’ve additionally created an summary texture, generated a nav mesh, and added a stage description, all of that are conveniently packed into the bsp itself for optimum comfort.” 

Zombie_City is obtainable to download from modding neighborhood GameBanana. It is a neat look again on the time Turtle Rock made one thing that impressed Valve a lot it acquired the studio, which might finally go its personal means once more to develop two extra co-op shooters: Evolve and Again 4 Blood.

Because of GamesRadar for the heads-up.