What Power Outage? Achievement in Halo: The Master Chief Collection

This achievement is actually best done cooperatively with only one other player. This is because when this mission is played solo or with two players, Mantises are provided as the means of vehicular firepower. When playing with three or four players however, these Mantises are replaced with Gauss Warthogs, which prove to be inferior to the firepower of a Mantis. With that said, each player should hop in their Mantises as soon as the mission begins and move through the canyon valley until they reach the group of UNSC Marines and two large generators. Take note that there are two extra Mantises on the platform behind the generators in the event that your starting Mech is destroyed.

The objective during this entire mission will be to protect both generators on the Forerunner platform from the oncoming waves of Covenant units. The Covenant will usually be dropped into the mission in one of two ways. Phantoms will drop small groups of six to eight Grunts off at the perimeter of the platform on both the left and right side while at other times, drop-pods will invite three to four Elites in the center of the platform.

Generally, there is no definitive guide that can detail the strategies involved with protecting the generators during this mission. Simply communicate with your teammate and utilize the firepower (machine gun turret and rocket pods) of the Mantis in order to eliminate the Covenant threat before they even have a chance to get near the generator and damage it with their weapons or melee attacks. Since the platform here is tight, each player should maintain their position on one end of the platform rather than pacing back and forth and getting caught on the walls. There are about eight waves of enemies that will storm the platform, but once they are all eliminated, the achievement will unlock before the mission requires players to proceed to the next mini-objective.