Sentinel Majors
From Halopedia, the Halo wiki
A type of Sentinel called the Enforcers. These mechanical giants have a variety of weapons. They shoot bombs from their back's,they also shoot red Needles. The key to an Enforcer's survival is their shield in front of them. Use plasma weapons to take down it's shield. Once it's shields are down let ur weapon rip!! Careful, because these Sentinel Majors have arms that can u pick you up. Overall be wary of this behemoth.