I highly recommend turning on invincibility and one shot kills.
First you have to get the mission "A matter of time" by speaking to a guy in logistics (containment level)
there's a guy named Horowitz due west of the logistics control point in the contamination sector at the very far end. He is on the ground, to the left of a shelter door and right beneath a sign that says "Shelter Service hatch."
I think you need levitation before the quest appears (comment suggests otherwise).
After completing A matter of time you will get another quest called "The enemy within". Return to "Sealed Threshold Hall" and open the vault in the main room with all the clocks. This is the same room that has the Lantern for another quest. This vault leads to an item that leads to the boss. One shot, when the red ball reveals itself, and the achievement's yours.
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https://guides.gamepressure.com/control/guide.asp?ID=51297Note: T
his achievement lagged for me and took a few minutes to pop, after completing the quest.