There are more Half-Life games besides the main 6, and you can play these for absolutely free (and legally)! The games listed here cover everything from utterly bizarre to breathtaking, and vary in degrees of officiality / canon. All of them are worth trying out.
MINERVA and Someplace Else are parts of an episodic fanmade mod set in the Half-Life 2 universe. Despite it being an original mod, there have been rumours that Valve might integrate it into the Half-Life and Portal canons. It features a GLaDOS-like main character that was developed two years before Portal was even a glint in Eric Wolpaw’s eye. You can get it through the official website, which has both download links for Steam and Desura.
HL2: Survivor is an arcade port developed by Valve, published by Taito in 07. It is tailored for Japanese audiences, and that means exactly what you expect. Alyx(?) sporting cat ears, engrish, and a quaint bastardization of the spirit of the original game. It is ridiculous fun. The gameplay is a class-based arena using the original HL2 maps, similar to TF2 (Gordon is in the “engineer” class. Guess he decided to change professions!) There is now a PC port that you can play, courtesy of the Facepunch people. Follow the instructions carefully and it should run with no problems!
- 3. Half-Life Alpha V 0.52 (9/4/97)
In the year of our Lord 2013, Reddit user Jackaljayzer bought a strange disk on Ebay for $700. It turned out to be a one-of-a-kind alpha version of Half-Life 1. It includes a deathmatch demo, a gorgeous tech demo, and a very unfinished first half of the game proper. All of it is fully playable. You can grab it here. And yes, it seems to be perfectly legal. Valve are aware of it and they havn’t spoken a word against it.
What Lost Coast is to HL2, Uplink is to HL. It was a chapter that was meant to be in the main game, but was later cut and distributed as a demo instead. You can get it here, with full integration into Steam.
This mod was illegal until 2009, so you can feel edgy playing it! It is not Beta HL2, but rather the reconstructed maps shown in the 2003 E3 presentation of Half-Life 2, which seem to have been created just for that purpose and never intended to be in the final game itself. You can grab a Steam install here.
The mythical stolen Half-Life 2 version. This one is still technically illegal, but a legal mod conversion can be found here. It is basically an unfinished Half-Life 2, which at times can be as hilarious as you expect.
A Half-Life co-op released for the PS2, now ported by modders for PC. They have Valve’s blessings and it’s perfectly legal.
It’s not a Half-Life co-op conversion, but its own game - you play as doctors Gina Cross and Colette Green rather than Gordon Freeman on new maps. If you are playing with a bot, expect to have to switch views often because the AI isn’t that incredible. The real gem in this game is the bonus vortigaunt chapter, Xen Attacks, in which you can play as an alien. You can get the mod port here.
Modders’ response to the shoddiness that is Half-Life: Source. It’s a complete remake of the first Half-Life, with triple-A title quality. It fully respects the soul of the original game, while breathing new life into it. The graphics are absolutely stunning. You can download it here both for Steam and Desura. It will soon have its own Steam storefront page, complete with Steam achievements!
- 9. Half-Life 2: Lost Coast
Probably the best-known title in this list. Lost Coast is a Half-Life 2 demo that you can get on Steam for free, and originally a chapter in the main game that got cut. It is absolutely visually stunning.
Developed by Nuclear Vision in 2003 and distributed by Valve, Codename: Gordon is a 2D side-scrolling version of Half-Life 2. The plot follows the story as shown in the 2003 E3 presentation videos rather than Half-Life 2 proper. It has since been removed from the store as Nuclear Vision went bankrupt in 2008, but it is still available for Steam install through a direct link.
A semi-official fanmade coop mod for Half-Life 1. It’s been around since the very beginning of Half-Life, and nowadays has an absolutely massive community that continuously produce goldsrc content. Besides being able to play Half-Life with friends, there are tons of other maps and sub-mods to try. You can grab it here for Steam. It will also soon have its own storefront page!
Co-op for Half-Life 2. Ever wanted to fight the combine with friends? Now you can! You can also get it directly on Steam.
- 13. Portal: The Flash Version
Like Codename: Gordon, but with Portal. It’s a 2D re-imagining of Portal, featuring its own characters. You can play it here. Don’t forget to check out the map pack once you finish it!
A retro-chic, ridiculously cute Half-Life flash game, based on Bobby is Going Home, a 1983 title for the Atari 2600. It was developed by the famous Andrew Kepple. You play as Lamarr, who must find her way back to Dr. Kleiner after being accidentally teleported far away. The cuteness is misleading: This game is very challenging. You can play it here!
- Honorable mention! Half-Life: Dreamcast
The Dreamcast port that never was. It was fully developed, but distribution was cancelled on the very eve. Fortunately, a good gentleman called Marphy Black got hold of the files and ported them to PC. There are only a few differences between the original PC Half-Life and the Dreamcast version, which is why it didn’t quite make the list.