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Equipped with advanced power armor and a characteristically bad attitude, he was the bane of privates, chastising them for the slightest mishaps and breaches of protocol, especially if he didn't like them.
In-game, it is best to steer clear of him, as talking to him while equipped with advanced power armor will end with you being forced to stand guard at the hangar. If you initiate dialogue with him while you are supposed to be guarding the hangar, he won't be pleased at all.
Should he spot you out of Enclave armor, there is a chance he has you thrown off the base, thinking you are just another civilian. However, with enough points in your primary and secondary statistics, you can fool him into believing that you have actually lost it or were not issued one by sloppy base personnel, resulting in a lengthy speech and a dismissal to the Quartermaster for another suit. Either way, you get armor.
Arch Dornan appears only in Fallout 2, however Cannibal Johnson in Fallout: New Vegas makes a reference to Dornan, remembering him for once catching a private out of uniform and going on the most "ear-blistering rant known to man."
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