At the end of Dragonflight's first raid, Razageth the Storm-Eater succeeded in freeing her brethren, the Primal Incarnates, from their prison, only for her to be slain in the process.

The encounter in question is Spine of Deathwing, the second to last encounter of the Dragon Soul raid in Cataclysm. If you are struggling to solo this encounter, here is how you can complete it.

The largest addition to World of Warcraft in the 4.3 patch is a Deathwing raid. The raid will feature multiple phases including flying in the sky.