Consolidating his forces with careful strategy, Ardashir Babakan led a hardened army of twelve thousand battle-tested horsemen toward the fortress of the formidable Worm. He positioned his troops securely in the strategic passage between two mountains and placed them under the command of Shahrgir, a wise and seasoned general. Ardashir instructed Shahrgir to maintain vigilant day-and-night sentries, saying: 'I shall now execute a alchemy of stratagem reminiscent of my ancestor Esfandiyar at the Brazen Fortress. When you behold a thick column of smoke rising by day, or a blazing beacon like a sun by night, know that the Worm's reign is extinguished and its star has fallen; advance instantly with the host.'
Ardashir then handpicked seven trusted, fearless champions who held absolute discretion. Disregarding worldly wealth, he gathered fine silks, gold, jewels, and treasure, but also packed two heavy chests with lead and tin, alongside a massive bronze cauldron. Dressing himself and his companions in humble coarse wool, disguised as humble caravan merchants, he also enlisted the two loyal young villagers who had previously sheltered him as guides and advisors.
Approaching the citadel of the Worm under the guise of a merchant from Khorasan, Ardashir was intercepted by the sixty dedicated attendants who served the beast day and night. When asked what lay hidden in his chests, Ardashir replied that he was a merchant bearing rich textiles, pearls, and gold, whose fortunes had flourished thanks to the auspicious grace of the Worm, and who had returned to offer tribute and devotion. Won over by his words, the attendants opened the fortress gates.
Once inside, Ardashir unladen his goods, distributed gifts among the servants, and prepared a lavish feast with fine wine. When the attendants who fed the Worm its daily diet of rice and milk initially declined the wine to tend to their duties, Ardashir stepped forward. He humbly requested permission to feed the Worm himself for three days to gain its divine blessing, promising to construct a magnificent palace nearby. Enticed by his generosity, the guardians indulged in the wine until drunkenness paralyzed their senses.
As the attendants fell into a stupor, Ardashir and his companions kindled a fierce fire beneath the bronze cauldron and melted the tin. When the Worm gaped its jaws and extended its copper-red tongue to receive its feast, Ardashir poured the molten, searing metal straight down its gullet. The liquid tin tore through the monster's bowels, causing a shuddering, violent crack to echo from its throat that shook the entire citadel. Drawing their swords, Ardashir and his warriors put the drunken guards to the blade, lit a dark signal fire upon the roof, and sent smoke billowing into the sky to summon Shahrgir and the Persian host to victory.