Durin's Bane

Balrogs /ˈbælrɒɡz/ are fictional creatures who appear in J. R. R. Tolkien's Middle-earth legendarium. Such creatures first appeared in print in his novel The Lord of the Rings, where the Fellowship of the Ring encounter one known as Durin's Bane in the Mines of Moria. Balrogs figured in Tolkien's earlier writings that appeared posthumously in The Silmarillion and other books.

Balrogs are described as tall and menacing with the ability to shroud themselves in fire, darkness, and shadow. They frequently appeared armed with fiery whips "of many thongs", and occasionally used long swords. In Tolkien's later conception, they could not be readily vanquished—a certain stature was required by the would-be hero. Only dragons rivalled their capacity for ferocity and destruction, and during the First Age of Middle-earth, they were among the most feared of Morgoth's forces.

According to The Silmarillion, the evil Vala Melkor corrupted lesser Maiar (angelic beings) to his service in the days of his splendor before the making of Arda. These became known as "Demons of Might": Valaraukar in Quenya, and (with an anglicized plural) Balrogs in Sindarin.

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