Following the passing of King Zou, his kinsman Garshasp ascended the Kayanid throne and placed the royal crown upon his head. Yet this fleeting interlude of peace was soon cut short by death, leaving the throne of Iran vacant once more and causing the tree of vengeance to bear bitter fruit. When news of the empty throne reached the Turanians, a fever of ambition swept their lands. Pashang, the ruler of Turan—who had long shunned his fierce son Afrasiab in grief and rage over Afrasiab's treacherous murder of his own brother Aghriras—saw the golden opportunity. He dispatched a stone-hard message urging Afrasiab to cross the Oxus River (Jayhun) and claim the Iranian realm before any sovereign could take the throne.
Afrasiab assembled a colossal host stretching from the plains of Spijab to the banks of the river. The earth trembled beneath their march like a churning sky, and the dust raised by their horsehooves blotted out the sun. As news of Afrasiab's advance at Khar-e Ray sent shockwaves across the land, the noble chieftains of Iran hastened to Zabulistan to seek aid from Zal. They lamented that since the days of Sam, no guardian had stood to shield them, and if Zal did not act, the nation would perish.
Zal answered them with deep solemnity, revealing that decades of relentless warfare had bent his back and stolen the strength of his arm. Yet he offered them grand hope: Rostam had grown tall and formidable as a soaring cypress, ready to bear the mantle of greatness. Desiring to test the young champion's spirit, Zal spoke to Rostam of the grueling hardship ahead, questioning whether one so young, still sweet with the innocence of youth, was truly ready for the horrors of war. Rostam replied with fiery resolve, declaring that his mighty arms and tiger-like strength were not nurtured for luxury or wine-cups. He vowed that with Divine favor, he would wield a blade like a stormcloud raining blood, asking only for a mountain-like steed and a mace heavy as a crag to crush the Turanian warlords and sweep the invaders from the sacred soil of Iran.