Relief of Hormizd II
The equestrian victory of Hormizd II (r.303-309) is immediately below Achaemenid tomb II (Artaxerxes?) and a vanished relief of Shapur II. It shows how king Hormizd unhorses an enemy, who may be identified with king Papak of Armenia, or perhaps one of the kings of the Kushans in the far east.
Louis Vanden Berghe, Reliefs rupestres de l' Iran ancien (1983 Brussels), #76.