|Affiliation and military information|
|Affiliation||United States Marine Corps|
Staff Sergeant Rainer was one of the Marines in charge of perimeter defense of Central Station during the Battle of Libery City. His men were ordered to demolish the lower foundation of the ONYX building in order to block Ceph mortar fire from hitting Central Station. When Alcatraz arrives in the area, he orders him to reset the breakers on the explosives, as the detonators are not setting them off. Once Alcatraz re-activates them, Rainer orders him to vacate the building. One of his men, Torres, attempts to detonate the explosives, but is overrun by Ceph before he can. Rainer orders someone to retrieve the detonator and detonate the explosives, which Alcatraz does. When Alcatraz returns, Rainer tells him to head inside to meet with Barclay.
Rainer is only seen in the level Unsafe Haven . He gives the player most of their objectives, but is never seen in combat, except right after he meets with the player, and right before the end of the level. His weapon is a Ranged SCAR. He looks and sounds the same as most common Marine characters that fight along the player, and his tactical description, which is seen with the visor, is also the same. He never leaves the area where the player meets him, and will only fight if Ceph units get inside his limited field of view. Aside from this, he is no different than any other Marine character.