Black Mesa

Black Mesa is a fan-made remake of Half-Life utilizing the Source engine as a standalone game. All key areas and events of the original game have been recreated faithfully, however there are a number of changes and tweaks that allow this game to be called re-imagining rather than a remake. These differences include: multiple changes to the maps - some have been altered and expanded, while others (including on-rail levels) were considerably shortened; new voice overs recorded for all the characters with many new dialogue lines added; the number of unique NPCs has been increased considerably; HEV suit's flashlight battery is now infinite; enemy's AI and weapon damage have been tweaked; a new weapon (flare) has been added; achievements have been introduced etc.

The version released in September 2012 contains 14 chapters of the original Half-Life, excluding the last several chapters that take place in the alien dimension Xen. It is now considered a Legacy release, being replaced by Black Mesa on Steam. This version is still available via the official website, it just no longer receives updates.