Half-Life Opposing Force-Missing In Action

Adrian Shephard continues his journey through Black Mesa in search of both his comrades and an alternative escape route after being abandoned at the extraction point. After battling Xen creatures,traveling through a zombie-infested blast furnace and fighting the Race X for the first time,Shephard meets several other Marines from his company who have also been left behind. He joins forces with them as they try to escape from the facility.