Battle of al-Qādisiyyah
According to one report, on one occasion during the Roman–Sasanian War of 421–422, the force attacked a Roman army, and although becoming outnumbered, they stood firm and were killed to the last man. Kaveh Farrokh calls the unit "Zhayedan", writing in his "" that they were used often against the Arabs in the 7th century (such as in the Battle of the Bridge and the Battle of al-Qādisiyyah).