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You know how to fight while surrounded by foes and can quickly instruct an ally on how to move in concert to survive against an overwhelming number of foes.
Choose an ally within 5 feet. Until the start of your next turn, as long as that ally remains within 5 feet of you and is able to take actions, and both of you are unmounted, you and your ally increase your AC by 2.
In addition, each of you gets an extra reaction that can be used before the start of your next turn to either make anor activate a combat maneuver.