In time, King Goshtasp set out toward Sistan to propagate the sacred teachings of the Zand and Avesta, intending to make the mobads and sages of that realm witnesses to the new faith. As the sovereign reached the borders of Nimruz, Rostam—the world-seasoned champion and peer of Sam—alongside his venerable father Zal and the chieftains of Zabulistan, rode forth to receive him with great ceremony. They welcomed the king into their lands with homage, learning the precepts of the Zand, donning the sacred girdle, and kindling the sacred fires. For two whole years, Goshtasp remained as their honored guest, feasting in harmony with the son of Zal.
Yet across the realm, a quiet rebellion began to stir. Reports spread that the king had bound his own guiltless hero-son, Esfandiyar, in heavy iron chains before departing for Zabulistan. Discontent flared; provincial rulers renounced their allegiance and broke their covenants with the Crown. Bahman, the noble son of Esfandiyar, along with the princes of Kianian blood and veteran warriors, laid down their arms in sorrow and rode toward the prison-fortress to comfort their bound lord, refusing to abandon him to solitary exile.
News of this rift reached Arjasp, the ruler of Chin and Turan. Spies informed him that Goshtasp, driven by unfounded suspicion, had cast Esfandiyar into prison and retreated to Zabulistan, leaving Balkh guarded only by the elderly Luhrasp, seven hundred fire-worshipping priests, and a handful of palace guards. Sensing that fortune had delivered Iran into his hands, Arjasp summoned the lords of Chegel to prepare for war. To confirm the intelligence, he dispatched a sorcerer named Sutuh—a master of hidden paths and subtle lore—to scout Balkh. Sutuh slipped undetected into the city, verified Goshtasp's absence and the capital's defense, and returned to lay his findings at Arjasp's feet. Overjoyed, Arjasp cast off his long-held grief and ordered his commanders to gather their scattered horsemen from every mountain, desert, and pasture to unleash a devastating assault upon Iran.