The development team behind the Black Mesa mod have commenced what they are calling a social media campaign that will conclude with the game's long-awaited release.
A new screenshot gallery is the mod team's first public statement on the project after prolonged and puzzling four-year silence.
The images have been posted below.
The Half-Life modification has been in development since 2004 and in recent years was increasingly branded as a "vapourware" game that would never be published.
But over the weekend, an update on the game's official website revealed that new media with key information would be released as soon as the Black Mesa Facebook fan page hit 20,000 'Likes' - a feat that was achieved early on Monday.
No final release date for the project has been set.
Black Mesa is a revisit to the first Half-Life game, though rebuilt from the ground up with the engine behind the 2004 sequel Half-Life 2. It is believed the game will stay faithful to the core narrative, level structure and design philosophies of the source material.
The game's first trailer was released in 2005, and three years later it was announced that the mod would be released in 2009. At one stage it was suggested the game would be free, of which there have been no claims to the contrary throughout the development cycle.
Black Mesa's core development team has shifted during the eight years of development, and the team's correspondence with Half-Life studio Valve is thought to be minimal.
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