Black Mesa a massive fan project 15 years in the making, to remake and overhaul the original half-life in the source engine improving both the graphic and gameplay quality. An experiment carried out by the Anomalous Materials department of the Black Mesa Research Facility had gone awry triggering a resonance cascade that allowed extradimensional aliens to invade the facility. In the middle of it all Dr. Gordon Freeman He must fight his way through the facility and escape the carnage.  

• General improvements: graphic overhaul, voice acting overhaul, the AI is also significantly updated and modernized although not too much that would alter the original spirit of the game.
• Complete the 19-chapter single-player campaign and fight through top-secret labs, harsh desert landscapes, abandoned railways, and the completely improved Xen dimension.
• The original half-life’s 10 multiplayer maps are also restored including Bounce, Gasworks, Stalk yards, Undertow, Crossfire, etc.
• Workshop integration: Create your own mods with the Black Mesa Source SDK and share it around the steam workshop.

Reviews

Black Mesa may show its age in some areas, but that doesn’t detract from what is an otherwise stunning achievement. It’s not only Half Life at its best – it’s one of the finest shooters available today.

Attackofthefanboy.com  

A quality remake that broadens the scope of the original and massively improves its final chapters.

Pcgamer.com  

Whether you played Half-Life back in the day or not, Black Mesa is definitely the best way to experience one of the crown jewels of first-person shooter history. It doesn’t look like a 2020 remake – because it’s not, really – but it still makes great use of the distinctively creepy atmosphere and excellent combat that left such a mark on this genre. And what better way to get ready for Valve finally returning to the Half-Life universe?

Ign.com