Black Ops

Black Ops, sometimes hyphenated to Black-Ops, are a commando group briefly seen in Half-Life and later expanded upon and featured in its expansion pack Half-Life: Opposing Force. Working independently of the Hazardous Environment Combat Unit (HECU), Black Ops invaded the Black Mesa Research Facility to conceal any evidence of the resonance cascade.

Half-Life
Black Ops first appear in Half-Life during the chapter Apprehension, and later make one more appearance during the chapter Lambda Core. Only Female Black Ops (also known as Female Assassins, and affectionately dubbed as "Sniper Babes" by some fans) are seen by Gordon Freeman in the game.

Female Black Ops are strikingly nimble and agile, able to sprint faster than any other enemy and can jump to extreme heights. They wear a black jump suit and use night vision goggles that include a headset with microphone, although none are ever heard speaking. They are armed with a silenced Glock 17 and grenades. At close range, they use an array of kicks to fight the player. When playing under the hardest difficulty level, female Black Ops have a cloaking field which they use to become invisible during combat, only revealing themselves when moving.

Female Black Ops were originally intended to be armed with crossbows as a weapon. The quivers they used to hold their bolts can still be seen on their belt in the final game.

The distinction between the Hazardous Environment Combat Unit and the Black Ops was not made at first in the original Half-Life. Although the two groups never encountered one another in the game, female assassins were coded to fight on the same side as the Marines. Many players assumed this meant they were working with the military since assassins had no backstory, and as such, many fan-made maps included them fighting alongside each other. It was not until the release of Opposing Force that more insight regarding the Black Ops was revealed.

Half-Life: Opposing Force
Black Ops are featured much more prominently as enemies in Gearbox Software's expansion pack Opposing Force. The reason for their presence at Black Mesa was also explained, something that was never made clear in the original game. Opposing Force explains that, after the initial failure of the HECU's clean-up operation, the Black Ops were sent to cover up the whole incident by destroying the entire facility. To do this, they intended to set off a thermonuclear device within the complex. Adrian Shephard locates the bomb the Black Ops delivered in a parking garage and is able to disarm it, but shortly thereafter it is seen being reactivated by the G-Man. The flash of a nuclear explosion is later witnessed, indicating the successful detonation of this bomb.

During gameplay, Black Ops are shown to have utter contempt for the HECU Marines, considering them incompetent and inept. One soldier angrily remarks to another, "Why do we always have to clean up a mess the grunts can't handle?" The Black Ops act hostile towards Marines, killing any who have not yet escaped as part of their mission. HECU radio traffic shows that the Marines were at first totally taken by surprise, much like how the HECU initially overwhelmed the Black Mesa personnel. Further evidence of their viciousness can be seen after discovering a Marine engineer who, after being brutally beaten and interrogated, is simply left for dead, trapped in a room by the Black Ops operators.

Along with the female Black Ops, Opposing Force introduced the group's male variant. Male Black Ops (also known as Male Assassins) wear black combat gear and ski masks that only expose their eyes. Some are seen wearing night vision goggles. Although not visible, they apparently have a communicator in their ear which they are seen listening to whenever they eliminate a target.

They are equipped with the same MP5 (M4A1 Carbine with the High Definition Pack) with grenade attachment that the Marines use, but some male Black Ops have a M40A1 sniper rifle. Black Ops utilize equipment and vehicles, such as trucks and Apaches, similar to the HECU, but black in color.

Black Ops soldiers can run much faster than the Marines, and up close, they use martial arts kicks and punches as melee attacks. Also, unlike their Marine counterparts, Black Ops operate in total silence when in combat, refusing to even yell in pain when injured.

Trivia

 * A characteristic given to the female Black Ops in the original Half-Life, one held to much amusement by fans, was a highly exaggerated bounce of the characters' breasts when she walked. This was removed in Opposing Force and in the PlayStation 2 console port of the original game.
 * Female Black Ops make a very small appearance in Half-Life: Decay's bonus mission "Xen Attacks", where they battle the players' two Vortigaunt characters in the same parking garage area that the Black Ops eventually place their thermonuclear device in. They do not appear within the main Decay missions themselves, however.