Long before the Great Cataclysm, which divided the face of Azeroth into the continents (Kalimdor and The Eastern Kingdoms) and Islands (Northrend and Kezan) that we know today, the 5 aspects of flight (black, red, green, blue, and bronze) ) they were tasked with a commendable task: Guarding the young world of Azeroth.
Sindragosa at that time, was the beloved Consort of the Aspect of the Blue Flight Malygos also known as the Spell Weaver, guardian of Arcane magic.
Aided by some goblins, Neltharion (also known as To the death) created a powerful artifact called the Dragon Soul. With tricks, he convinced his brothers to empower the disk by assuring them that with this power he could stop the invasion of the Burning Crusade.
However, Neltharion betrayed his brothers during the Legion's assault, sparking a massive battle in the skies over the Well of Eternity. Malygos and Sindragosa joined their companions from the blue flight to defeat Neltharion, the Protector of Earth. They charged the mighty black dragon but it harnessed the power of the Dragon Soul to defend itself, killing almost all the Blue Dragons.
The blast threw Sindragosa far across the continent, leaving her in the icy northern tip. Blind and knowing her death was near, Sindragosa headed for the Dragonblight, the place dragons instinctively travel to die. Unable to fly, Sindragosa crashed into the frozen lands of the Icecrown region. The blue dragon gathered what little energy she had left and called out to Malygos for his help. Her only response was the intense howl of the artificial cold as she screamed.
Dying, Sindragosa realized that her spirit would find no rest outside of the Dragonblight. His life was fading and his sanity was dwindling more and more. Delirious, Sindragosa's last feelings were bitterness and hatred: hatred towards the Legion, hatred towards Neltharion and even hatred towards Malygos. But above all, I hate the mortal world.
And in her last moments ... Sindragosa cried out for revenge.
Your wishes can be seen fulfilled thanks to the mighty Lich King who, in the place of her death, raised the spirit of Sindragosa, making her Queen of the Frost Wyrms.