Halo Wars 2

This achievement is earned during Mission 4, "The Archive."

At the very beginning of this mission, you will be prevented from venturing deeper into the facility due to a Forerunner defense system that blocks the way. The only way to navigate past these lasers is to use the nearby control panel and power them down. After this, you will come in contact with five more laser defenses throughout the mission: the first will require you to use Voridus and the Elite Rangers to turn off the lasers that block the Jump Pack Brute's path; the second and third require one of your more agile units such as Elite Rangers or, later, the Honor Guard, to zigzag through a maze/grid of moving lasers and reach the control panel to shut them off; the fourth set of lasers is more of a roadblock, and can only be turned off after surviving a large wave of Flood in a circular chamber; the fifth and final set of lasers is much like the third set in that you will need to use one of your units to navigate through a maze/grid that moves across the ground. If, by this point, you lost your Elite units and do not have enough resources to call them in, Voridus himself can "tank" his way through the lasers due to his shields and high HP.

Overall, this is a relatively easy achievement so long as you use an agile unit such as Elite Rangers when moving through the maze-like laser grids. If if you do not have the Nightmare skull activate, you can also save before attempting to pass through the laser grids. Should your units get zapped by a laser, you can restart your checkpoint and try it again. Once you've re-activated the Sentinel defenses and completed the mission, the achievement will unlock provided you did not lose any units to the Forerunner defense systems.