"How fortuitous. Usually, I must leave me lair in order to feed."Onyxia
was a black dragon, the daughter of Deathwing, and sister of Nefarian
. With the disappearance of their father, command of the Black Dragonflight had fallen on the two siblings. To that end, Nefarian took control of Blackrock Spire, overtly ruling over its inhabitants and establishing it as a stronghold for the Black Dragonflight. Onyxia, meanwhile, established a lair for herself in Kalimdor, claiming a vast swath of Dustwallow Marsh and driving out the resident ogres in order to secure a safe place for his offspring to grow.
While the victory of Nefarian's forces against the Dark Iron Dwarves seemed inevitable, Onyxia saw the greatest threat to the Black Dragonflight's holding was from the human nation of Stormwind. In order to ensure the success of the Black Dragonflight, and likely to secure more power for herself, Onyxia took the guise of Lady Katrana Prestor and infiltrated the royal court of Stormwind.
As Katrana Prestor, she quickly rose to power, gaining considerable influence within the Court of Nobles. At this time, the Stonemason's Guild had just completed the reconstruction of Stormwind, repairing the damage the city had sustained during the First War. Working from behind the scenes, Lady Prestor was convince many of the nobles that they didn't actually need to pay the stonemasons for their work. The leader of the Stonemason's Guild, Edwin VanCleef
was outraged by this decision, and demanded that he and his people be properly compensated for their work. King Varian was able to convince both parties to sit down and talk, but was unable to reach any sort of agreement that made both the Court of Nobles and the Stonemason's Guild happy. Varian was able to get the stonemasons paid for their work, but it was considerably less than they had been promised. Edwin VanCleef, along with much of the Stonemason's Guild, outraged by this perceived treachery, stormed out of Stormwind. Forming the Defias Brotherhood, Edwin established a secret base within the Deadmines, and plotted his revenge.
Onyxia recognized King Varian as being the greatest impediment to her taking control of Stormwind. When he left to travel to Theramoore to discuss Alliance-Horde relations with Jaina, Onyxia arranged for him to be captured by agents of the Defias Brotherhood. While the Defias agents were successful in kidnapping Varian, they ended up shipwrecked in Dustwallow Marsh. Varian ended up on Alcaz Island as a prisoner of the naga until he mysteriously disappeared one day.
With King Varian missing, Bolvar Fordragon
was named Regent of Stormwind, with Lady Prestor serving as his advisor. She was quick to take control of Bolvar, charming him with magic and making him much more willing to heed her advice. Despite there being no evidence for King Varian's death, Prestor was able to convince Bolvar to have Varian's son, Prince Anduin, crowned as King of Stormwind.
With Stormwind effectively under her control, Onyxia did much to sabotage the kingdom. She withdrew support of the Stormwind Guard from many of Stormwind's provinces, leaving the towns of Moonbrook, Lakeshire, and Darkshire to fend for themselves, and allowing the problems facing them to grow out of control. Soon, Moonbrook fell under the control of the Defias Brotherhood, along with much of Westfall. Many of Moonbrook's former residents took shelter at an old watchtower, known as Sentinel Hill. Duskwood was soon overrun by worgen and the undead, with the village of Raven's Hill all but abandoned. Lakeshire was left to fend for itself against the Blackrock orcs, who watched helplessly as the orcs took control of Stonewatch Keep, a bastion meant to protect Lakeshire from attack from the Burning Steppes, and transform it into their base of operations in the region.
Marshal Reginald Windsor, a knight of Stormwind commanding a small force in the Burning Steppes, was able to learn that the Black Dragonflight had an agent controlling the Kingdom of Stormwind from within. Realizing that it could only be Lady Prestor, he planned to confront her and reveal the truth. Fortunately for Lady Prestor, he was captured by the Dark Iron dwarves before he could do so. "Curious... Windsor, in this vision, did you survive? I only ask because one thing that I can and will assure is your death. Here and now."
Unfortunately for Lady Prestor, he was eventually rescued by adventurers, who were able to recover Windsor's confiscated notes. Together, the adventurers and Windsor returned to Stormwind. Lady Prestor ordered Windsor's arrest, however the Marshal was able to convince the guard not to do so. He arrived in the throne room and confronted Prestor, forcing her to assume her true form. Revealed to be a black dragon, Onyxia killed Windsor and fled, retreating to her lair in Dustwallow Marsh.
Bolvar, freed from Onyxia's control, ordered the adventurers to slay the dragon. After reforging the Drakefire Amulet, the key necessary to access her lair, a group of adventurers raided it and killed her, taking her head as proof of the deed. Her head was then mounted on the gates of Stormwind.
When King Varian returned in Wrath of the Lich King, Lady Prestor was removed from Stormwind's throne room, along with Bolvar. As part of the WoW's Fifth Anniversary Celebration, Onyxia had her level increased from 60 to 80. Curiously, WoW's Fifth Anniversary was November 23rd, 2009, just two days from now. Onyxia's presence so close to that date seems to suggest that Blizzard had planned to revamp her lair well in advance."Ha ha ha ha ha! The heroes have made it to the glorious finale! I take it you are in good spirits? Prepared for the final battle? Then gaze now upon my ultimate creation! RISE, SISTER!"
-Lord Victor Nefarius
Upon his return to Azeroth, and unleashing the Cataclysm, Deathwing raised his son, Nefarian, from the dead. While it was in his power to restore Onyxia as well, he saw no need to. While he could make use of Nefarian's scientific knowledge and various mad experiments, Onyxia's manipulations had already been played out. Nefarian, however, saw the unfairness of this and took matters into his own claws. Using his scientific prowess, and new found interest in undeath, he recovered his sister's head and body, connected them, and transformed her into a mindless electric powered zombie dragon. He then unleashed her upon adventurers who attempted to raid his new lair, deep beneath Blackrock Spire. She was destroyed once again, and Nefarian soon after.