The 2nd Shock Troops Battalion was a formation of the UNSC Marine Corps and the Orbital Drop Shock Troopers. Members of Alpha Team, 3rd Unit of the Battalion operated during the ground engagements at the Battle of Sector Six in Pakistan during the late stages of the Battle of Earth where at least one was killed by Covenant forces while trying to stop enemy advances. The unit was identified by an IFF Tag seen through a security camera when pointed at one of the Marines.