Durin's Bane

"You cannot pass. I am a servant of the Secret Fire, wielder of the Flame of Anor. The Dark Fire will not avail you, flame of Udûn. Go back to the Shadow! You cannot pass."

- Gandalf (Book Two: Chapter V)

Durin's Bane refers to a Balrog of Moria of the Third Age who was not otherwise named but an important figure during the War of the Ring.

History
Durin's Bane was one of the Maiar spirits that existed before the creation of the world (similar to Gandalf and Saruman), who descended into Arda with the Valar. It was eventually seduced and corrupted by Melkor, becoming known as one of the Valaraukar, and it then joined with the other Balrogs in Morgoth's service. The Balrog fought in many battles of the War of the Jewels and fought in the War of Wrath. It somehow managed to survive Morgoth's defeat and fled east and hid itself beneath the Misty Mountains.

For more than five thousand years, the Balrog hibernated in its deep hiding place at the roots of the mountains in Khazad-dûm. It remained undisturbed throughout the Second Age and most of the Third Age, before the Mithril-miners of Dwarf-King Durin VI awoke it when they mined too deeply, in search of mithril. Durin was slain by the creature, at which point it became known as Durin's Bane.

The Dwarves attempted to fight the Balrog, but its power was far too great. Despite their efforts to hold Khazad-dûm against it, King Náin and many of the Dwarves were killed and the survivors were forced to flee. This disaster appears to have also reached the Silvan Elves of Lothlórien, many of which also fled the "Nameless Terror" (it was not recognized as a Balrog at the time). The elves began to call the place Moria, "The Dark Abyss."

For five hundred years, Moria was left to the Balrog. Sauron began to put his plans for war into effect around the year TA 2480 of the Third Age, and sent orcs and trolls to the Misty Mountains to bar all of the passes. Some of these creatures came to Moria.

It is unclear as to whether Sauron could have controlled the Balrog (they were both Maiar) but it's possible that they could have allied against the Free Peoples. The Balrog did allow the Orcs and trolls to remain in Moria while it dwelt there. Tolkien does not mention whether Sauron was aware of the Balrog's presence prior to this time.

The Battle of Azanulbizar was the climactic battle in the War of the Dwarves and Orcs. It took place before the eastern gate of Moria in TA 2799 and was a victory for the Dwarves. However, the victors did not conquer Moria, because Dáin II Ironfoot, having slain the orc Azog, felt the terror of the Balrog at the gate. Despite an attempt to recolonise Moria by Balin in TA 2989, Durin's Bane remained a menace in the ancient kingdom of the Dwarves whose nature was hidden to the outside world.

In January of TA 3019, the Fellowship of the Ring travelled through Moria on the way to Mordor. There, they encountered Durin's Bane at the Bridge of Khazad-dûm. The Elf Legolas instantly recognised the Balrog, but more importantly, the wizard Gandalf happened to be there. Knowing that it was far more powerful than even the greatest of his companions, Gandalf challenged it. Since Gandalf and the Balrog were both Maiar, they were beings of the same order. The Balrog attacked first with its flaming sword, which Gandalf destroyed with Glamdring. Gandalf then smote the Bridge before him with his staff. The staff broke asunder, a blinding sheet of white flame sprang up, and the bridge cracked at the feet of the Balrog, who fell forward into the abyss. As the Balrog fell it swung its whip. The thongs of the whip wrapped around Gandalf's knees, dragging him after the Balrog. "Fly, you fools!" Gandalf cried, and was gone.

As they fell, the Balrog's flames burned Gandalf. After the long fall, the two landed in a subterranean lake, which Gandalf later said almost froze his heart. The water quenched the Balrog's fire, but now he was "a thing of slime, stronger than a strangling snake". Gandalf fought the Balrog, and eventually the Balrog fled, and Gandalf pursued the creature until they came to the Endless Stair and climbed to the peak of Zirakzigil, or Celebdil, at which point the Balrog's bodily flames were renewed, restoring much of its power. There, beginning on January 23, they fought what was later known as the Battle of the Peak. Gandalf prevailed and slew the Balrog, casting it down and sending it crashing into the mountains. Then "darkness took" Gandalf for a time (whether this means he actually died is open to debate) but then he "was sent back – for a brief time, until my task is done." The great eagle Gwaihir the Windlord (lord of the Great Eagles of Middle-earth) found him and carried him to Lothlórien where he was healed and clothed in white – he had become Gandalf the White.

The ultimate fate of Durin's Bane is not known, as only its physical form died, as with all Maiar when they were "killed," but what happened to the spirit of the Balrog was not revealed. It is also unknown if it was the last of its kind, or if there were other Balrogs who managed to escape the War of Wrath and remained hidden in long forgotten places.

Portrayal in adaptations

 * Durin's Bane appears in Ralph Bakshi's Epic Battle Gandalf vs. the Balrogted film, and follows Tolkien's description in that it is bigger than a man, but not huge. However, its appearance has been mocked by reviewers, noting that it appears to have wings similar to a butterfly, appears to have fuzzy feet, has the head of a lion-like creature, and roars repeatedly. After its fall into the chasm of Khazad-dum, it changes into a half snake, half demon like creature.


 * The Balrog was also portrayed in Peter Jackson's live-action film trilogy, where it was a large, black creature covered in flame. Although Tolkien described it as being a little taller than a man, Durin's Bane in the film was much larger than a man, at least eighteen feet or so. Rather than having a voice of any kind, when it roared, it sounded similar to an erupting volcano - the vaporous presence of heat emanating as its breath. Its weapons, rather than physical in nature, were completely comprised of flame, taking the form of a sword first and a whip second. More than its use of obliteration, it was flames that were its key weapon of choice against Gandalf.

Video Games
In The Fellowship of the Ring video game, Gandalf battles the Balrog with his lightning bolts and then with his sword.

In Battle for Middle-earth, the Balrog appears as a boss in the first level. The player is forced to fight the Balrog solely with Gandalf, using his Lightning Sword strike multiple times to kill it.

In BFME II, another Balrog appears in Dol Guldur (how it is summoned is not known) but the combined efforts of the Elves and Dwarves successfully defeat it.

In the Evil mode, the Balrog can be summoned using its respective power. The Balrog can ignite its sword to cause additional melee damage, strike with its whip, roar to cause enemies to flee in terror, fly to certain areas, and most importantly, blast enemies and structures to ashes with its incinerate skill. The Balrog, not surprisingly, is deadly in melee.

The Balrog is both a boss and a playable hero in The Lord of the Rings: Conquest. In the Good campaign, the player must kill it to reclaim Moria from the Orcs. In the Evil campaign, it appears twice: once to kill Gimli, and once to kill Treebeard. Its weapon in this game is a flaming sword and Fire Breath.

Two Balrogs also feature in The Lord of the Rings Online. The first one, called Thaurlach, was created for the purposes of the game, and is the last 'Boss' in the famous Rift Raid, a 12-player instance in the region of Angmar. The other Balrog, Durin's Bane, features in one of the introductory quests to the Mines of Moria expansion of the game; an illusionary copy of it can later be fought in the Fear Wing of the Ost Dunhoth raid.

The Balrog will appear in the LEGO Lord of the Rings game. While it's fight against Gandalf remains the same as in the film, it belches at one point, causing Gandalf to wave the fumes away in disgust.

The Balrog is a main boss in the Lord of the Rings: The Third Age where it initially appears in a cut scene at the bottom of a mithril mine and is later fought on the bridge of Khazad-dûm where Gandalf becomes a temporary party member.