Black Mesa is a first-person shooter video game, developed and published by Crowbar Collective. It is a third-party remake of Half-Life (1998) in the Source game engine. Originally published as a free mod in September 2012, the game was given approval by Valve (the developers of Half-Life) for a commercial release. The commercial version was first published as an early access title in May 2015 and had its full release in March 2020 for Microsoft Windows and Linux, with future plans for a macOS version.
Black Mesa was developed in response to Half-Life: Source (2005), Valve’s port of Half-Life to the Source engine, which lacked new features or improvements. The project was formed by the merging of two separate teams that wanted to improve on the Source remake, eventually becoming Crowbar Collective. While they had originally targeted a release by 2009, the team realized they had rushed to this point, and reevaluated their efforts to improve the quality of the remake.
Since then, attention to details, adapting the game to an improved version of the Source engine, and completely reworking the oft-derided final chapters of Half-Life known as Xen had lengthened the development efforts into the remake. Due to its long development time, the modification became notable for its delays on the status of its completion. Among major changes in the remake include reskinned collection of textures, models, and NPCs; a longer runtime; improved level and puzzle design along with challenging enemy artificial intelligence, and additional dialogue and story elements.
Black Mesa received positive reviews upon its initial release and was lauded as the game was updated and improved. Praise was directed towards the gameplay and attention to detail, comparing it to that of an official Valve release, as well as for the improvements they had made on the Xen chapters.