When King Piruz ascended the Kayanian throne, he embraced the path of righteousness and divine devotion, urging his nobles to cultivate wisdom, patience, and boundless mercy. Yet trial soon beset the realm: a devastating seven-year drought gripped the land of Iran. Springs withered, the air grew as dry as ash, and famine cast its shadow over all living creatures. Demonstrating extraordinary royal compassion, Piruz remitted all taxes, unlocked the crown granaries, and ordered the wealthy to sell their grain at affordable rates so that no soul would perish of hunger. In the eighth year, the king led his people out into the open plains in fervent prayer; the heavens answered with torrential rains, bringing the earth back to vibrant life.
Following the end of the famine, Piruz dedicated himself to restoring the realm, building and fortifying cities such as Rey and Bad-an-Piruz (Ardebil). Driven by ambition for martial glory, he mobilized a grand army against Khushnavaz, ruler of the Hephthalites, scorning the ancient boundary treaty stone erected by Bahram Gur at the River Oxus. Khushnavaz raised Bahram's written covenant atop a spear, pleading with Piruz not to break a sacred oath and invoking God as his witness. Yet Piruz remained obdurate and rejected all peace envoys. In defense, Khushnavaz ordered a vast subterranean trench to be dug and concealed across the battlefield. Charging headlong, King Piruz, his brothers Narsi and Farrukh Qobad, and seven allied monarchs tumbled into the hidden abyss, perishing in the trap. Prince Kavadh (Qobad) was taken captive in iron chains, and a tide of grief washed over the grieving realm of Iran.