When Rustem heard this, he cried with a voice of thunder, "I am Rustem!" and the warrior, who had no desire to fight the champion of the world, turned his back and fled. But Rustem pursued him, and thrust at him with his lance where the belt joins the coat of mail, and pierced him through, for the armor could not turn the point of the great spear. Then he lifted him out of his saddle, and raised him up in the air, as if he were a bird which a man had run through with a spit. This done, he dashed him down dead upon the ground, and all the nobles of Mazanderan stood astonished at the sight.
After this the two armies joined battle. The air grew dark, and the flashing of the swords and clubs flew like the lightning out of a thunder-cloud, and the mountains trembled with the cries of the combatants. Never had any living man seen so fierce a fight before.
For seven days the battle raged, and neither the one side nor the other could claim the victory. On the eighth day King Kaoüs bowed himself before God, taking his crown from his head, and prayed with his face to the ground, saying, "O Lord God, give me, I beseech thee, the victory over the Genii who fear thee not."
Then he set his helmet on his head, and put himself at the head of his army. First of all Rustem began the attack, charging the center of the enemy's army. He directed his course straight to the place where the King of Mazanderan stood, surrounded with his chiefs and a great host of elephants. When the King saw the shine of his lance, he lost courage, and would have fled. But Rustem, with a cry like a lion's roar, charged him, and struck him on the girdle with his spear. The spear pierced the steel, and would have slain the King, but that by his magic art he changed himself, before the eyes of all the Persian army, into a mass of rock. Rustem stood astonished to see such a marvel.
When King Kaoüs came up with his warriors, he said to Rustem, "What is it? What ails you that you tarry here, doing no thing?"
"My lord," answered Rustem, "I charged the King of Mazanderan, spear in hand; I struck him on the girdle, but when I thought to see him fall from his saddle, he changed himself into a rock before my eyes, and now he feels nothing that I can do."
Then King Kaoüs commanded that they should take up the rock and put it before his throne. But when the strongest men in the army came to handle the rock, or sought to draw it with cords, they could do nothing; it remained immovable. Rustem, however, without any one to help him, lifted it from the earth, and carrying it into the camp, threw it down before the King's tent, and said, "Give up these cowardly tricks and the art of magic, else I will break this rock into pieces."
When the King of Mazanderan heard this, he made himself visible, black as a thunder-cloud, with a helmet of steel upon his head and a coat of mail upon his breast. Rustem laughed, and caught him by the hand, and brought him before the King.
"See," said he, "this lump of rock, who, for fear of the hatchet has given himself up to me!"
When Kaoüs looked at him and observed how savage of aspect he was, with the neck and tusks of a wild boar, he saw that he was not worthy to sit upon a throne, and bade the executioner take him away and cut him in pieces. This done, he sent to the enemies' camp, and commanded that all the spoil, the King's throne, and his crown and girdle, the horses and the armor, the swords and jewels, should be gathered together. Then he called up his army, and distributed to them rewards in proportion to what they had done and suffered. After this he spent seven days in prayer, humbling himself before God, and offering up thanksgiving. On the eighth day he seated himself on his throne, and opened his treasures, and gave to all that had need. Thus he spent another seven days. On the fifteenth day, he called for wine and cups of amber and rubies, and sat for seven days on his throne, with the wine-cup in his hand.