Valve accidently leaks Left 4 Dead prototype in Counter Strike update

Often game updates have unintended consequences, but few are as strange or cool as what has just gone down in Counter-Strike.

A prototype build of Left 4 Dead has been found inside the files for CS 1.6 and after banding together the community has worked out how to play it. As you’d expect, the game looks like a very old, unpolished state of what Left 4 Dead ultimately became, but it’s an interesting glimpse into the past of Valve’s hits. News of this find and footage of gameplay from the mode dubbed “Terror Strike” was shared on social media by Counter-Strike content creator Gabe Follower. In the clip we see players shooting enemies in a wide-open city as they venture to a location and plant a bomb. Once planted the objective changes to defending this location from the hordes of enemies.

The interesting thing about this build is that it doesn’t yet have zombie enemies, instead, it’s just Counter-Strike players with knives. However, you will still hear the shrieking noises of zombies that you’ll remember from Left 4 Dead. While this find is very cool, even at a glance you can tell it was very far from being a finished product. Newcomers to the Counter-Stike franchise with CS2 might not be familiar with CS 1.6. This is the first entry into the Counter-Strike series and still has an active community despite being dated, bringing in around 10,000 players every day. Because of this consistent player base, it still gets updates, but often they’re very minor. The latest of these updates landed on Nov. 22.

Similarly, many newer gamers might not even be familiar with Left 4 Dead and if you fall into that category there’s no better time to explore that franchise than right now. You can get both the first Left 4 Dead and its iconic sequel on Steam right now for less than $5.