Gothmog

Gothmog was the Lord of Balrogs during the Ancient Times of Izumo and was the greatest Balrog ever to walk Dens.

Abilities
Gothmog, like the rest of his kind, carried a fiery whip into battle, but he was also known to have wielded a great black axe.

Birth of Shinseijū Tree
Using seeds from the fruit of of Tree of Knowledge Good and Evil it was discovered that by fusing massive amounts of chakra—such as that of a tailed beast—with the seed, would then cause it to activate and grow. The result was a tremendous tree with massive amounts of chakra. Gothmog was one of the Maia who swore under the allegiance of the Black Demon. During the Era of Shinseijū, the X Clan Leader pressed to Angband with his company, and in that hour, the Balrogs were issued forth. Gothmog was among them, smiting the High King of the Ñoldor to the ground. The Sons of Fëanor arrived and carried the body of their father away, but Fëanor had passed.

End of Creation Arc
Gothmog reappeared as a general of Angband in several more major conflicts, including the Dagor Aglareb and the Nirnaeth Arnoediad. During the Nirnaeth, Gothmog engaged the High King of the Ñoldor, Fingon, in battle. Gothmog separated Fingon from the main host but was unable to smite Fingon, until another balrog appeared behind the Ñoldo "cast a throng of steel about him". This allowed Gothmog to slay Fingon and beat the body to dust. Thereafter, he captured Húrin, father of Túrin Turambar, and dragged him back to Angband. Gothmog and the forces of Angband laid siege on the Hidden City of Gondolin. They held the northern gates and was later confronted by Ecthelion of the Fountain. Knocking Ecthelion's sword out of his hands, Gothmog prepared to strike at him but, as he raised his axe, Ecthelion ran forward at the Balrog lord, ramming his pointed helmet into the beast's chest and forcing both of them into the Fountain of the King. The waters quenched the flames of Gothmog that kept him alive and drowned Ecthelion, ending the Battle of Gondolin.

Trivia

 * His Name and his reputation came from Gothmog from the lord of the rings series.