Taerar

Taerar is one of the four Dragons of Nightmare.

Dragons of Nightmare
In recent times, Ysera's most trusted lieutenants have been warped by a dark new power within the Emerald Dream. Now, these wayward sentinels have passed through the Great Trees into Azeroth intending to spread madness and terror throughout the mortal kingdoms.

Taerar was perhaps the most affected of Ysera's rogue lieutenants. His interaction with the dark force within the Emerald Dream shattered Taerar's sanity as well as his corporeal form. The dragon now exists as a specter with the ability to split into multiple entities, each of which possesses destructive magical powers. Taerar is a cunning and relentless foe who is intent on turning the madness of his existence into reality for the inhabitants of Azeroth.

Cataclysm
With Emeriss and Lethon already dead, Ysondre asks for help from players to kill Taerar during a quest chain in Feralas. With that grim task finished, Ysondre is the last of the former Dragons of Nightmare, and although she has been saved from the nightmare, she states she can never return to the green dragonflight. She hopes that one day, she will be able to live a simple life, hidden among mortals.

Legion
When Ysondre is taken by the Emerald Nightmare once again, the corrupted spirits of her deceased comrades join her in the Emerald Dreamway, including Taerar. After the defeat of Xavius, Taerar's spirit along with the spirits of the other three former Dragons of Nightmare are seen in the restored Emerald Dream.

Objective of

 * Taerar's Fall