Black Operations are the agents sent in after the HECU Marines to dispose of evidence surrounding the resonance cascade in Half-Life 1. Encounters are exclusively female agents in the base game, but male variants were added in Half-life: Opposing Force. They wear all black covering their bodies, and often wear night visiongoggles. Female black ops only have silenced handguns and grenades, while male black ops can possess a wider range of guns.
