When Half-Life launched in Nov. 1998, it was actually a redesigned version of the game. What came before was quite different and got leaked back in 2013 as Half-Life Alpha 0.52. Now it's easily playable in enhanced form thanks to the work of a modding team.
As the Half-Life Wiki explains, Half-Life Alpha 0.52 was discovered when the contents of a disc got shared in Jan. 2013. It showcased all of the single-player levels, had three weapons with unlimited ammo, two trailers, and ran on a modified version of the Quake engine. It offered a distinctly different experience to the Half-Life we all know while still remaining true to the same storyline.
It's possible to play through that 0.52 build as the video above proves, but it's not the easiest game to get running. Now, however, a new mod not only makes experiencing the Alpha easy, it improves upon it.
As PCGamesN reports, the modder known as Jackathan on ModDB has made available a Half-Life mod called In Deep. It's described as, "In Deep takes you through the scrapped version of Half-Life from 1997, re-imagined and revamped. What awaits you is a surreal, fast-paced, and action-packed journey through the old Labs once again!"
The mod goes a step further, though, and while not straying very far from the original design and layout, Jackathan and a small team have made, "the puzzles less mindbendingly awful and the combat more reminiscent of the retail version of the chapter." Game-breaking bugs have been removed, the environments "prettied up a bit," and overall it's a "less linear and somewhat extended version of Office Complex from retail Half-Life."
The In Deep mod is a 7.4MB download and in order to work must have its "hlid" folder copied into the Steam/SteamApps/Common/Half-Life/ subfolder. It's sure to be an interesting experience for fans of the original game and a welcome distraction while we await the release of Half-Life: Alyx in March next year.