Operation Counter-Strike

Operation Counter-Strike is the name of the covert mission in Quake's plot, launched by the United States government in secret to enter the newly discovered slipgates, and find and destroy Shub-Niggurath (code-named Quake, in absence of the knowledge of her real name) to preempt an invasion force hitting Earth.

Ranger, being their "best man," was in charge of the Operation, but the whole operation was put to an untimely end when a raid on the secret slipgate installation left all of the friendly marine forces defeated or corrupted, and Ranger was left as the only survivor of Quake's massive coordinated attack, being forced to enter the slipgates alone.