Many are the mysteries surrounding the Emerald Dream and its reclusive guardians, the green dragonflight. In times past, druids have entered the Dream to monitor the ebb and flow of life on Azeroth in their quest to maintain the balance of nature. However, not all dreams are pleasant ones. Emerald Nightmare, an area of corruption within the Emerald Dream, began growing in size, transforming the Dream into a realm of unimaginable horror. Green dragons have been unexpectedly caught up in the Nightmare, emerging from it with shattered minds and twisted bodies. Druids who have entered the darkening Dream lately have found it difficult - sometimes even impossible - to escape. Nor are these the Nightmare's only victims - more and more people are being affected. Even Malfurion Stormrage, first and foremost of the druids on Azeroth, may have fallen victim to this growing threat. As uncontrollable nightmares spread across the world, a desperate quest begins to find and free the archdruid.