Fulad-zereh meaning "[possessing] steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 armor," is the name of a huge horned demon in the Persian story of Amir Arsalan

Amir Arsalan

Amir Arsalan-e Namdar is a popular Persian legend which was narrated to Nasser al-Din Shah Qajar, the Qajar Shah of Persia in the 19th century, by a storyteller named Mohammad Ali Naqib al-Mamalek...

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Fulad-zereh made aerial wanderings and spotted and kidnapped beautiful women.

Early in his career he was the chief general of the fairy

Fairy

A fairy is a type of mythical being or legendary creature, a form of spirit, often described as metaphysical, supernatural or preternatural.Fairies resemble various beings of other mythologies, though even folklore that uses the term...

 king, Malek Khazen, who ruled over the land of Zahrgiah.

Fulad-zereh's mother, a powerful witch in her own right, used a charm to make Fulad-zereh's body invulnerable to all weapons except the blows of a specific sword called Shamshir-e Zomorrodnegar

Shamshir-e Zomorrodnegar

Shamshir-e Zomorrodnegar is a sword in the Persian legend Amir Arsalan. The witch mother of a hideous horned demon called Fulad-zereh used a charm to make his body invulnerable to all weapons except this specific sword.Shamshir-e Zomorrodnegar originally belonged to King Solomon, and was carefully...

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At the end of the story, however, both Fulad-zereh and his mother were slain by Amir Arsalan.