The Steam 'teraleak' extends far beyond Valve games, including prototypes of third-party titles like Mafia 2 and Grand Theft Auto 3: 'This may be one of if not the biggest leaks to occur'

On Saturday, information began circulating online about a massive, 12-terabyte leak of Valve data that included prototypes of numerous classic Valve games. But it seems what is now being dubbed the "teraleak" contained far more than just old builds of Portal 2 and possible weapons from Half-Life 2: Episode 3, and may include prototypes of countless third-party games released on Steam over a ten-year period.

Specifically, the leak consists of Steam file groups known as 'depots' which were stored on Steam's servers between 2003 and 2013. A full list of these depots was shared on Reddit by user RefreshingCapybara, which includes depot names for hundreds of games as well as trailers, teasers, soundtracks, demos, game trials, and more. "Not...