To unlock this achievement, you must brand 5 bodyguards of a Warchief, thus turning them against him in combat.

Once you have five Captains branded and counted as that Warchief's bodyguards (You can check by selecting the Warchief in the Sauron's Army menu and see if the five bodyguards that connect to him are the ones you branded), start the mission to kill him.

You'll have to complete some side objective to draw him out. Or if you're having his bodyguards betray him, he'll automatically be out in the field. When he shows up, I made sure to run up to him and have him recognize me and do his little intro.

Last, just press Up on the D-pad and the five captains around him will begin to attack. The achievement should pop a few seconds after you press Up on the D-pad.

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