Valve leaks Left 4 Dead's early prototype in the latest CS 1.6 update

In a new update for Counter-Strike 1.6, Valve appears to have accidentally leaked one of the earliest prototypes of what would become Left 4 Dead.

The details:

• Fans discovered that in the new update for CS 1.6, a mode called "Terror Strike" was included, most likely by mistake, which was essentially Turtle Rock Studios' prototype for what would later be L4D, complete with never-seen-before custom code.

• As seen in @GabeFollower's X post, the mode is very basic, with players tasked with planting a bomb in typical Counter-Strike fashion, then killing all waves of "zombies," who are simply counter-terrorists armed with knives. Although it feels far from L4D and more like a community-created mode for CS, it's fascinating to see the starting point of what would become a beloved series.

• The mode's map, "zombie_city," was discovered earlier this year and implemented into CS: Source by fans. It consists of only simple geometry and no textures, and it had to be ported to 1.6 by a user named "The One Epicplayer," who also added the zombie navigation mesh.

More gaming news:

• Battlefield V has experienced a massive resurgence in popularity on Steam, where its price has been cut by 92% during the platform's autumn sale. On November 23, the concurrent player count reached nearly 78,000, the highest since 2021.

• Ubisoft has provided a quick update on the remake of Prince of Persia: The Sands of Time, confirming that the project is progressing well after being handed over to Ubisoft Montreal earlier this year.