Half-Life: Blue Shift, commonly referred to as Blue Shift, is the second stand-alone expansion pack for Half-Life, developed by Gearbox Software and was released on June 12, 2001. Like Gearbox's other expansions, Half-Life: Opposing Force and Half-Life: Decay, Blue Shift returns to the setting and timeline of the original story, but with a different player character: the ubiquitous Black Mesa Research Facility security guard Barney Calhoun. As Barney, the player attempts to escape the alien invasion caused by the resonance cascade and the ensuing military cover-up.
Blue Shift has now been released via Steam for $4.99. Originally, anyone with access to the back catalog, whether through an old copy of Half-Life or the Silver or Gold packs of Half-Life 2, could download Blue Shift for free, but this has since been discontinued.
A fan mod is currently in the works that will see the whole game remade in the Source engine currently titled Guard Duty.
The Blue Shift package offers the Half-Life High Definition Pack as an option at the time of install. The pack includes updated 3D character, weapon and item models, often increasing the polygon count 10-fold over the 1998 originals. The U.S. Blue Shift release includes a full, stand-alone version of Opposing Force, but the international edition has the multiplayer-only Opposing Force CTF.
Blue Shift started out first as an exclusive part of the Half-Life Sega Dreamcast port. Due to Sega pulling the plug on the Dreamcast, and the subsequent abandonment of the platform by nearly every major publisher, this version was cancelled only weeks away from release (the Dreamcast Half-Life port has since been leaked onto the Internet, with both Half-Life and Blue Shift fully playable). Gearbox then turned the project into a stand-alone product; unlike Opposing Force, it does not require the original Half-Life.
Although fans of Half-Life were eager to play more of their beloved game, many complained that Blue Shift did not measure up to the high standards set by the Opposing Force expansion. The game offers some new levels and areas of Black Mesa previously unseen in a relatively short new campaign, but no new weapons or enemies, as Opposing Force offered. Aside from the High Definition Pack, the only new content was a character named Rosenberg, a Black Mesa scientist who has his own unique character model and played a major role in the story, and alternate scientist and security guard models wearing civilian attire. Blue Shift reviews were very poor in comparison to other games in the series.
On August 24, 2005, Blue Shift became available for download via the Steam content delivery program. Anyone who owned an old copy of Half-Life, or the Half-Life 2 Silver or Gold packages (thus, having access to the back catalog) could download it for free. Since then, access to Valve's back catalog for free after registering a previously owned copy of Half-Life has been discontinued, and Blue Shift must now be bought either alone, as part of the Half-Life 1 Anthology, or as part of the Valve Complete Pack. The High Definition Pack is also available via Steam.
The Steam port suffers from numerous issues, most probably because the GoldSrc engine used in the game has been changed, preventing Blue Shift maps from being correctly played. Additionally, the Steam port omits the fixes from the Blue Shift patch that prevent known map and model glitches. The Steam port also introduced several other bugs that did not exist in the original release, such as the graphical user interface color now being displayed in the standard Half-Life orange, not Blue Shift blue. A third-party mod, Blue Shift: Unlocked, addresses these issues and can successfully patch files from either a CD or Steam version of Blue Shift. But many of the issues have already been fixed in recent updates to the game.
- Barney Calhoun
- Walter Bennet
- Gordon Freeman (Cameos)
- Wallace Breen (Indirect mention only) (Retcon)
- The G-Man (Cameo)
- Gina Cross (Cameo)
- Adrian Shephard (Mentioned only)
- Black Mesa Science Team
- Black Mesa Security Force
- Crowbar: A simple melee weapon that is iconic of the Half-Life series.
- 9mm Pistol (Beretta M9 pistol with the High Definition Pack and Glock 17 without): The first and simplest ranged weapon. It has good accuracy and does more damage per shot than the MP5, but these advantages are offset by a low rate of fire that makes it more useful on weak targets, like headcrabs or laser tripmines. Unlike most other ranged weapons, this pistol is effective underwater. Primary fire is accurate with every shot; secondary fire uses the rapid-fire function, and is faster but less accurate. The rate of fire is then comparable with the MP5, but does slightly more damage per shot. The 9mm Pistol is the standard equipment of the Black Mesa Security Guards; Calhoun would obtain it before the crisis unfolds.
- Colt Python: An extremely powerful and accurate gun. It has a long reload time and a 6-round cylinder. Good for dispatching enemies in one hit, especially from a distance.
- Submachine gun / Assault Rifle (High Definition Pack) (Heckler & Koch MP5/M203 grenade launcher, Colt M4A1 Carbine/M203 grenade launcher with the High Definition Pack): Excellent for close-range combat. Has a fast rate of fire that compensates for its poor damage and accuracy. Secondary fire launches an extremely powerful under-slung grenade that detonates on impact. It uses the same ammo pool as the pistol.
- Shotgun: Does high damage at close range, but its broad fire cone makes it weak at a distance. It can be reloaded one shell at a time, but is slow to fully reload. Its secondary fire shoots two shells at once. The shotgun is the additional equipment of the Black Mesa Security Force, stored in the security armory, however Calhoun would not be able to get one before the crisis.
- Rocket propelled grenade (RPG) launcher: Does a large amount of explosive splash damage. Secondary fire toggles a laser designator that guides the RPG to its target. Can only hold one rocket at a time with 5 more in reserve.
- Hand grenade (Mk. II Fragmentation Grenade): A frag grenade that explodes a few seconds after being thrown. Can be bounced off of walls. Useful for killing enemies behind cover or softening up bigger targets.
- Satchel Charge: A high-explosive that can be thrown a short distance and detonated when the player presses fire. Secondary fire allows the player to place several satchels and detonate them simultaneously.
- Snarks (alien weapon): Small, aggressive alien creatures that quickly pursue their target, pestering and biting, until finally exploding after several seconds (or if shot). If they cannot locate a hostile target, they will turn on the player that set them loose. When used in numbers, they are very effective at drawing enemies out from their cover, or distracting them from attacking the player.
- Flashlight: Cut item. Seen in an Early Trailer . In the final game it only usable as a non-weapon mechanic, in a similar fashion to the HEV Suit's flashlight.
Blue Shift: Unlocked
Blue Shift wasn't initially available on Steam like Half-Life and Opposing Force. In August 2005, the Half-Life Improvement Team released a mod that ported the legacy version of Blue Shift to Steam, allowing the player to play it as a fully working mod for HL1 rather than its own stand-alone game. This had the added benefit of letting Blue Shift take advantage of features that had been added to the GoldSrc engine since then, such as detail textures. Almost immediately after, Valve made Blue Shift officially available—but it used its original engine, and suffered from many of the same bugs as the legacy version. A few months later, the porting project was updated, and renamed to Blue Shift: Unlocked.
- Blue Shift has its own version of the Hazard Course training tutorial, suitably adjusted for security personnel. Instead of Gina Cross, a male security guard identified in the instruction manual as Miller serves as the holographic guide.
- Similar to the game Black Mesa; a third-party remake of Blue Shift in the Source engine is in development under the name Guard Duty.
- Despite being created by Gearbox, none of the new weapons featured in their previous expansion Opposing Force are in Blue Shift. The player cannot even obtain all of the weapons from the original Half-Life.
- When using the code "sv_chaseactive 1" to go into the third person the player will see Gordon Freeman instead of Barney Calhoun.
- Interestingly enough, the model has the same ponytail as Gordon's model does in Half-Life: Opposing Force, but also lacks the sunglasses.
Blue Shift received a mixed reaction from critics, holding overall scores of 67.40% and 71/100  on the review aggregator sites GameRankings and Metacritic, respectively. The game has sold around 800,000 copies at retail (this figure does not include later sales on Steam). In a review for IGN, critic Tal Blevins noted that Blue Shift's gameplay "is pretty much what we've come to expect out of Half-Life" by blending action and puzzle solving, stating that the latter "were all logical and well done, although some of the jumping puzzles were frustrating". Though IGN praised the game for maintaining the "epic" feel of the original, Blevins was critical of the relatively short length of the game. GameSpot reviewer Greg Kasavin agreed with many of IGN's criticisms, stating that "it's not that the game is easy so much that it's extremely short" and that Blue Shift "doesn't amount to much on its own terms". In addition, Kasavin described the graphical enhancements brought about by the High Definition pack as "helpful", but noted that "they still don't make Half-Life look like a new game—nor are many of the changes themselves very noticeable".
Other reviews echoed complaints about the similarity of Blue Shift to previous games. GameSpy's reviewer Jamie Madigan stated that "what really pulls the game down is the 'more of the same' factor". Although writing that the game "feels like just a few more levels for the original game", he noted that this is what Blue Shift was designed to be, given its origins as an add-on for a Dreamcast version of Half-Life. Madigan described the single-player campaign as "decent" and commented that the High Definition pack made the game "worthy of consideration". Eurogamer echoed criticism on the game's length; reviewer Tom Bradwell commented that "although I'm hard pressed to criticize what you get, the complete absence of everything we've learnt from the likes of Counter-Strike and everything since is frankly bizarre". Bradwell did, however, criticize the game's artificial intelligence and the occasional bug that caused a player to get stuck on a wall. PC Zone's Mark Hill was more lenient in his comments, praising the game's artificial intelligence as "intelligent as you could hope an AI enemy to be". In addition, Hill praised the game for showing more activity in the base, noting that "a whole world goes on around you, with people eating at a cantina and scientists doing their laundry. The complex is more alive than ever before". Hill also praised the focus "on a greater interaction with scientists as proper people rather than the two or three models that were cloned throughout the facility who kept repeating the same phrases", describing this as Blue Shifts "greatest achievement". PC Zones review closed by commenting that "as a Dreamcast extra it works perfectly, but as a standalone PC title there's not nearly enough to it."
- "Half-Life: Blue Shift" on IGN Cite error: Invalid
<ref>tag; name "IGN" defined multiple times with different content
- Not Given Half A Chance: The Cancellation of Half-Life on IGN
- Half-Life: Blue Shift Released on Steam on Steam News
- Half-Life 1 Anthology on Steam
- Valve Complete Pack on Steam
- Steam Client Update Available on Steam News
- Blue Shift: Unlocked downloads from the Half-Life Improvement Team
- Half-Life Improvement Team
- Half-Life: Blue Shift game files (
- Half-Life: Blue Shift Reviews on GameRankings
- Half-Life: Blue Shift (PC: 2001): Reviews on Metacritic
- Analysis: Valve's Lifetime Retail Sales For Half-Life, Counter-Strike Franchises on Gamasutra
- Half-Life: Blue Shift on GameSpot
- Half-Life: Blue Shift Review on Eurogamer
- PC Review: Half-Life: Blue Shift on PC Zone
- Installing the Half-Life High Definition Pack for Steam (official)
- GameRankings.com: Blue Shift
- Blue Shift at Planet Half-Life
- Half-Life Improvement team, home of Blue Shift: Unlocked modification