Proof of Demise: Keristrasza

Objectives
Archmage Lan'dalock in Dalaran wants you to return with Keristrasza's Broken Heart.

This quest may only be completed on Heroic difficulty.
 * Keristrasza's Broken Heart

Description
Are you familiar with the story of Keristrasza?

How she was instrumental in the slaying of Saragosa, the mate of Malygos? How, in turn, he took Keristrasza as his consort, freezing her within a block of ice?

We have become aware that Malygos has been using his magic to break her will. This has driven her insane.

, you must go into the Nexus in Coldarra and put an end to her before she can be fully turned.

Though it saddens me, I must insist that you bring me her heart as proof.

Rewards
You will receive:

Progress
If we thought there was a way to redeem her, we wouldn't be asking you to put an end to her life.

However, we know how powerful Malygos's command over magic has become. With his manipulations of Azeroth's ley-lines, he is without peer where matters arcane are concerned.

Completion
Regrettable, but extremely necessary.

The Kirin Tor could ill afford a prominent red dragon falling into the hands of our greatest enemy. Malygos's use of her against us in the Nexus War would have been devastating.

I simply regret that we couldn't have saved her instead.