The plot of Black Mesa is almost identical to Half-Life's storyline. Like in the original game, the player controls Gordon Freeman, a theoretical physicist working at the Black Mesa Research Facility. He is tasked to place a sample of anomalous material into an Anti-Mass Spectrometer for analysis, using the Mark IV Hazardous Environment Suit (HEV Suit) to do so safely. However, the sample causes a "resonance cascade", devastating the facility and creating an interdimensional rift to an alien dimension called Xen, bringing its alien creatures to Earth.
Black Mesa (previously known as Black Mesa: Source) is a third-party total conversion modification for Valve Corporation's Source engine. The stated goal of the project is to recreate Valve's critically acclaimed 1998 video game Half-Life using the more advanced capabilities of the Source engine. The 40-person volunteer development team says they hope to create a more engrossing in-game world with more varied, complex environments and more challenging, realistic gameplay. During its eight years in development, Black Mesa has been featured in several video game publications and received direct attention from Valve. Due to its long development time the modification became notable for its delays, and dwindling updates on the status of its completion. The delays led to Wired awarding Black Mesa high spots on their "Vaporware Of The Year" lists in 2009 and 2010.
Gameplay:
Black Mesa is a first-person shooter that requires the player to perform combat tasks and puzzle solving to advance through the game. The core gameplay remains unchanged from the original Half-Life; the player can carry a number of weapons that they find through the course of the game, though must also locate ammo for most weapons. The player's character is protected by a hazard suit that monitors the player's health and can be charged as a shield, absorbing a limited amount of damage. Health and shield packs can be found scattered through the game, as well as stations that can recharge both.
Source: Wikipedia, "Black Mesa (video game)", available under the CC-BY-SA License.
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