Originally, we planned to claim the outer space for ourselves. Unrestrained use of every resource and infinite room for all human beings. But then, things did not turn out the way they should have. Nowadays, it seems our planet is the one to be conquered. Earth is in a state of emergency. The human race has been shrunk to a few hundred thousand. Our world is nearly completely destroyed. The area of the Black Sectors is spreading. Nobody knows from where the Wraith came. We know only one thing: They are damned deadly and frigging furious. But today – on July 6th, 2023 – the day has come for mankind to strike back. United Alliance’s government – formed by the heads of states of USA, Germany, Great Britain, Italy, France, Spain, China, Japan and Russia – decided to send the UASC, the United Alliance Special Corps, into the conflict areas to reclaim human habitat. The Wraith are dominating roughly 70% of world’s surface. In the meantime, men fortified in the biggest remaining megacities like London, New York and Tokyo – cut off from the environment, an enclave of fear, strongholds in the manner of forgotten times. Just to prevent human kind‘s last bastion from being annihilated. Play either as a soldier of the UASC in several classes (like Heavy Gunner, Warrior, Light Infantry or Sniper) or get control of the mysterious, unknown Wraith. Battle worldwide in the infested Black Sectors for global dominance. No compromises, no mercy.

Operation Black Mesa is a Half Life 2 modification; the second installment of the award winning Half Life. Utilizing the immense array of features of the Source engine, the Operation Black Mesa team plans to remake Opposing Force in all it's glory in the Source engine. What we plan to do is remake everything from the 3D models to the maps, so that Opposing Force can once again be praised as one of the best expansion packs for any game to date. We here at the Operation Black Mesa team wish to comprise both single-player and multi-player elements into our modification.