Mard ō mard (Middle Persian; literally "man to man") was an ancient Iranian tradition of single combat, the Sasanian Empire being most known for using it. During a battle, the Sasanian troops would use taunts and war cries to provoke the enemy into a single duel with a Sasanian champion. The tradition meant much to the Sasanians—in 421, during Bahram V's war against the Romans in 421–422, Ardazanes, a member of the "Immortals", was in a single duel killed by the Roman comes Areobindus, which contributed to Bahram V's acceptance of the defeat in the war and making peace with the Romans.