The Demon Soul, formerly known as the Dragon Soul, was an artifact created shortly before the War of the Ancients. Though it appeared to be a featureless golden disk, it was in fact a talisman of immense power created by the Aspect of the black dragonflight, Neltharion the Earth Warder... later known in history as the Black Scourge, Deathwing.
At some point shortly before the War of the Ancients, Neltharion used his own essence and the skills of his goblin artificer-servants to create an artifact of incredible power, in order to combat the invading forces of the Burning Legion. However - possibly due to his corruption by the Old Gods, who sought freedom from their imprisonment by the Titans eons earlier - Neltharion also wished to use it to control the other Dragonflights, and make himself a god to be worshipped by the mortal races. However, during an accidental cave-in that tore a scale from his body, Neltharion found that his matter - even as small as a scale - could damage the Soul (which it did), and thus he had to take great care to avoid damaging it. When it was ready, Neltharion revealed his creation to his fellow Aspects, and convinced them to give their own essences, which then made them and their flight unable to damage the disc.
In the last combined flight of the dragons of Azeroth against the Burning Legion, Neltharion arrayed the dragons of all the other flights into a magical matrix that enhanced the device's power greatly. During this battle, Neltharion revealed his madness and used the Dragon Soul to wreak havoc on both the Burning Legion and the helpless night elves, demanding that all of Azeroth, including the other dragon flights and the Great Aspects, bow to his mastery. Malygos, the Aspect of Magic, and his blue dragonflight attempted to stop Neltharion, who summarily executed the entirety of the blue flight with the exception of Malygos himself. The other dragons were locked in Neltharion's control until the unexpected intervention of Korialstrasz broke his concentration and allowed the other dragons to counter-attack. Though the ranks of the Dragonflights were decimated, Neltharion was forced to retreat from the field of battle, taking the Dragon Soul with him.
Neltharion's Corruption, and the Theft of the Soul
In time, it became clear that the powerful Soul was corrupting Neltharion's body, causing it to bloat and tear; his beloved creation was ripping him apart. With the aid of his goblin artificers, Neltharion had immense adamantium plates bolted into the scales in order to keep the destructive power at bay. Driven completely to madness, it is around this time (probably influenced by the future-Korialstrasz, known as Krasus) that the artifact became known as the Demon Soul, and that Neltharion received the name he is known by today. In order to prevent it from being used against them again, Broxigar, Korialstrasz (Krasus), along with the night elf druid Malfurion Stormrage, attempted to steal the artifact. Malfurion succeeded in obtaining the artifact, but was captured by Queen Azshara's soldiers...led by his own brother, Illidan, who had agreed to obtain the artifact to allow Sargeras entry into Azeroth.
The Soul was used as part of a portal to be opened within the depths of the Well of Eternity itself. Before the portal could be opened, however, the Soul's spellwork was disrupted and back in the possession of the resistors. After the Legion was banished from Azeroth and the Sundering of the World finished, Malfurion and the four remaining Aspects placed a spell on the Demon Soul that would prevent Deathwing from ever using it again, and then hid the foul disk in a place where only the four dragons would find it...but not Deathwing.
The Power Unleashed
Ten thousand years later, Deathwing - seeking to rebuild his shattered Dragonflight using the eggs of his archnemesis, Alexstrasza - found the Demon Soul and led the orcs of the Dragonmaw Clan to it. Nekros Skullcrusher, a former warlock, was entrusted with the disk by the Dragonmaw chieftain, the elder shaman Zuluhed the Whacked. With it, the Dragonmaws managed to capture the Dragonqueen, much to everyone's surprise (including Alexstrasza's), and use her children to fight for the Horde. Korialstrasz - in his guise as Krasus, a member of the senior council of the Kirin Tor of Dalaran - had discovered Deathwing's identity as Lord Prestor, and his revealing the location of the Soul to the orcs. Sending his student, Rhonin, on a mission to free Alexstrasza, Krasus attempted to obtain the aid of the other three Aspects - Malygos, Nozdormu and Ysera - to free Alexstrasza from the orcs...and subsequently from Deathwing himself.
Rhonin, who had been "rescued" by Deathwing twice during the course of his mission, was manipulated by the black Aspect to locate Alexstrasza and free her (or so he led Rhonin to believe). Giving him one of his scales to act as a talisman, allowing him to communicate with Rhonin and see what the human mage saw, Deathwing sent Rhonin on his way to Grim Batol. He finally discovered Alexstrasza's location, and the imminent moveout of the Dragonmaw Clan (under the belief that the Alliance intended to invade). As Deathwing held the upper hand in a battle with the other, weakened Aspects, including the now-free Alexstrasza, Rhonin was able to use the scale Deathwing had given him to destroy the disk. Cutting the scale across the surface, Rhonin unleashed the power trapped within...and with a quick spell, returned to the Aspects their essence given at the creation of the Dragon Soul, who proceeded to defeat and hunt their treacherous brother.
Resurfacing and Destruction
Though the Demon Soul's power was lost with its destruction, it still had enough power within it to be of some use. Sintharia, Prime Consort of the Destroyer, collected the fragments of the Demon Soul and found power within them still. Using their power combined with Balacgos's Bane, a stolen staff of the naaru and the essence of the nether dragon Zzeraku, Sintharia (or Sinestra, as she prefered to be called) experimented with the eggs of various dragonflights. The end result was the twilight dragonflight, a sinister creation that could absorb magical energy from any living thing - particularly enemy dragons. One such monstrosity, Dargonax, was a cunning and ambitious creature who sought to overthrow his "mother" and take the world for himself.
Zendarin Windrunner, a cousin of the Windrunner sisters, had allied himself with Sintharia in order to gain access to a vast fount of energy and steal the partially restored Demon Soul. Ultimately this brought him into conflict with his cousin Vereesa, who sought revenge for Zendarin's attempted kidnapping of her twin sons. The battle resulted in the death of Zendarin and the final destruction of the Demon Soul, when the naaru staff he carried touched the foul artifact as he released all of its energy. This was possible because Sintharia had shielded the artifact from all Azerothian magic, and the staff had been from Outland. Sintharia attempted to reconstruct it - having fallen to the same protective madness over the artifact as Deathwing had - but it was once again destroyed, this time for good, when it impacted with the unstable Balacgos's Bane thrown by Korialstrasz, obliterating both artifacts.
Whispers of Demon soul
- "The Night elves will destroy the World..."
- "The Well is out of control..."
- "No one can be trusted...they want your secrets, your power..."
- "Malygos would take what is yours..."
- "Alexstrasza seeks dominion over you..."
- "They are no better than the demons..."
- "They must be dealt with like the demons..."