Published by Crowbar Collective
1. The over 10 hour single player experience has greatly improved from the mod release; new visuals, new voice over, updated gameplay encounters, stability changes and more.
2. Black Mesa is the award winning re-imagining of Gordon Freeman's landmark journey through the Black Mesa Research Facility.
3. Expect tremendously detailed environments, old-school tough-as-nails combat, and a gripping story with memorable characters.
4. Xen is not part of the Early Access release, but will be included as a free update when it is ready.
5. Relive Half-Life in this highly acclaimed, fan-made recreation.
6. Shoot.
7. Source.