Durin's Bane

“Durin’s Bane” denotes the specific “Balrog of Morgoth” that dwelt within the deep gorges of Moria (also known as Khazad-dûm or the Dwarrowdelf), a hidden kingdom of the Dwarves underneath the Misty Mountains. Despite its unknown history or real name, nonetheless, this particular Balrog played a vital role in the "War of the Ring," when the dwarves of Moria awakened it unintentionally. When the first dwarven inhabitants of Moria abandoned their abode, the Balrog went back to sleep, only to be reawakened by the “Fellowship of the Ring,” again inadvertently. It is also during this time that it met its death through Gandalf, the Grey wizard.​

Long before the Earth’s creation, there existed spirits called Maiar, from which beings like Gandalf, Saruman, the Valar, and the Balrogs all came. Both the Balrogs and the Valar descended into Arda, and before long, Melkor was able to corrupt and seduce the particular Balrog, now known as Durin's Bane. It became one of the Valaraukar and joined the other Balrogs to serve Morgoth. The creature then fought in many wars, such as the War of the Jewels and the War of Wrath. When Morgoth was defeated, the Balrog survived, fled to the east, and hid underneath the Misty Mountains.​

The Balrog remained latent underneath the Misty Mountains and the Dwarves realm of Moria for about five millennia. It continued to be uninterrupted throughout the Second Age, and a considerable portion of the Third Age, until the Dwarves inadvertently disturbed its sleep in the year 1980. At that time, the Dwarves dug too deep and mined too greedily for mithril and awoke what was to become their doom.

The Balrog killed Durin VI in that year, and the following year, 1981 killed his son, Nain I, in the latter’s bid to destroy the creature. The Fellowship of the Ring journeyed through Moria to reach Mordor in January of the year 3019 of the Third Age. The orcs inhabiting the mines attacked the group in the Mazarbul Chamber, [1] so they escaped through a side door. As Gandalf was casting a spell to shut the door on the pursuers permanently, the Balrog moved into the chamber from the opposite side and cast its spell to counter the wizard’s spell. Gandalf uttered a command to keep the door open, but the door exploded, causing the chamber to break down. The group ran away with Gandalf, but the Balrog and the orcs, going on an alternate path, were able to catch them at the Bridge of Khazad-dûm. While on the bridge, both Legolas and Gimli recognized the creature as the Balrog (to Legolas) and Durin’s Bane (to Gimli).

Gandalf then ordered the Fellowship to cross the bridge with all haste, standing his ground in the middle to block the Balrog's way. The evil creature’s flames appeared to have died, but its darkness increased as it prepared to attack with its sword blazing in flames. The Balrog’s flaming sword seemed to melt into a red-hot metallic liquid as it clashed against Gandalf’s sword Glamdring. Having lost its sword, the Balrog conjured its whip, brandishing the new weapon while leaping onto the middle of the bridge.

In response, Gandalf struck the bridge with his staff, while shouting at the Balrog, “You shall not pass!” The staff broke apart into fragments, a sheet of blinding white flame sprung up, then the bridge fractured beneath the Balrog, hurling the creature into the chasm. Thinking the creature gone, Gandalf momentarily dropped his guard, turning to move towards his companions. However, as it fell, the Balrog lashed its whip, caught Gandalf by his legs, and dragged him off the bridge's edge and into the abyss. While plummeting a great distance, Gandalf and the Balrog struggled and fought, and after a long time, crashed into a vast underground lake (Gandalf later described its waters as cold as death’s tide and nearly had his heart frozen).

The lake’s waters extinguished the Balrog’s flames diminishing it to a slimy, snake-like beast, its strength somewhat decreased. Even in this weakened form, Durin’s Bane continued its attack on the wizard. The foes battled in the lake waters, the creature strangling Gandalf while he struck the beast with Glamdring until the Balrog escaped into ancient mysterious tunnels. Gandalf continued his pursuit of the Balrog outside Moria, catching up to it on Celebdil’s summit, where they waged a climactic battle. Ultimately, Gandalf killed the creature and hurled its carcass down the side of the mountain. Unfortunately, Gandalf succumbed to his battle wounds. The Balrog's final fate is not clear, given that only its body 'died,' as is usual of all Maiar when they 'expire.' The fate of the Balrog's spirit, however, is mostly kept unknown. Also not known is whether the creature was the last of its breed, or whether there were remaining Balrogs that survived the War of Wrath, remaining hidden in places long forgotten.​

In this animated film feature, the Balrog appears as a large lion (about 15 feet tall) with bat’s wings standing on two legs with hooves at the bottom. It has a human-like torso with arms and hands, holding a whip on the left and the flaming sword on the right. It also had a voice and could speak. [2]​

In Peter Jackson’s live-action adaptation of the adventure, the Balrog is shown as a large dark creature engulfed in flames. Tolkien described the beast as taller than the men in the Fellowship, but Jackson's version is enormous, 20 feet tall, or more. Jackson chose not to give it a speaking voice as a departure from earlier versions of the creature. Instead, he provided it with a roar that sounded like a volcano erupting, complete with the visual effect of heat vapor exuding from its mouth when it breathes and roars. The sound of its roar was ingeniously made by dragging a cinder block along a wooden board and digitally altering its recorded pitch. The Balrog's weapons, instead of having physical forms, were conjured from fire, first forming into a sword and, later, into a whip. However, these implements were only secondary to its primary weapon: its flames, which it employed effectively against Gandalf. The fight sequences in the film hold true to the ones in the book. Gandalf used both Glamdring and a magical shield conjured around himself, to parry and shatter the creature's flaming sword. Then Gandalf used his staff to smite the Bridge of Khazad-dûm, effectively destroying it, and made the Balrog plunge into the abysmal chasm below. Also, as it fell, the Balrog uses its whip to latch onto the wizard's legs and drag Gandalf below.​

Featured in a few flashback scenes in the second installment of the trilogy, the Balrog is seen in the events taking place after Gandalf plummets into the depths of Khazad-dûm. We witness Gandalf recover his sword while hurtling down the abyss. He catches up with the Balrog and strikes it with the sword, landing several blows while the creature tries to hit Gandalf with its claws and fists. The two opponents are locked in fierce battle as they plummet down into a vast subterranean lake. The Balrog’s flames are doused when they hit the water. In the next flashback scene, we see Gandalf and Durin’s Bane fighting at the top of Mount Zirakzigil in a fierce storm. Gandalf was able to infuse Glamdring with electric power from a lightning bolt and strikes the Balrog at the heart, inflicting a mortal injury. We last see the Balrog’s smoking carcass crashing down the mountain, its fires extinguished.​