Lambda Core Level A image - Half-Life: Dark Matter mod for Half-Life

You are Kovac, a senior agent in the covert Special Black Operations unit. You're deployed to Black Mesa to halt the next phase of the science team's plan after HECU forces are unsuccessful in stopping Freeman from launching the Omega Satellite delivery rocket... ...but you fail, the procedure ends up creating massive portal storms in the sky sending you and your team through a void to oblivion and back. You wake up almost twenty four hours later; the military has withdrawn, and everyone and everything besides your fellow Black Operators are now a target. To make matters worse, another hostile and more powerful alien faction has appeared in the chaos, further complicating the situation. The incident can no longer be contained, you must link up with other Black Ops units and prepare to wipe the facility from the map once and for all...