Fully playable Left 4 Dead prototype discovered 15 years later

A treasure trove of Counter-Strike maps recently leaked onto the internet, including a mod that was the predecessor to the cooperative survival game. Left 4 Dead. The mod is uniform fully playableas long as you know how to set up your own server.

According to the game leaker streamer Tyler McVickerthe prototype originated as a game mode in Counter-Strike: Condition Zero. Players would gather in groups of up to four people and play as terrorists. The objective was to plant a bomb while defending against waves of infinitely respawning hordes of counter-terrorists. These enemies only used melee attacks, making them the perfect predecessor to L4D zombies

The developers at Turtle Rock Studios clearly thought the mode had a lot of potential. They polished it further during the development of Counter-Strike: Source, where it was renamed “Terror Strike”. L4D director and Turtle Rock co-founder Mike Booth confirmed the mod’s existence. via Twitter. “It was our favorite lunchtime game,” he wrote. “We wanted Valve to release it, but for whatever reason we never got traction.” Turtle Rock was known as “Valve South” after it was acquired by Valve in 2008. They had already started co-op development for survival, but had no advocate within the parent company.

Former Valve writer Chet Faliszek said Kotaku that Turtle Rock had already begun work on L4D before he got involved. The game caught his attention and he became his “champion”. “I was one of the people who reviewed it and told Gabe at lunch,” he said. “I did a lot about it, he said he should go work on it.” As a result of his involvement, he was able to increase the scope of his output. Faliszek recruited over a hundred Valve developers to L4D after the company acquired Turtle Rock.

Valve published the zombie survival co-op in 2008. A sequel followed the following year, Turtle Rock eventually parting ways with the publisher and becoming an independent studio in 2011.

It’s pretty good that such a prolific game originated as a mod that its creators were personally passionate about, rather than a carefully planned product. If you want to see what L4D seemed in its ideation stage, you can download the mod here.