We’re looking at a work-in-progress cutscene of Alexstrasza and Raszageth that plays in the Waking Shores.

The cutscene shows Alexstrasza and Raszageth, the final boss of the Vault of the Incarnates raid. Courtesy of art_prominence. We’ve covered the entire story of the Waking Shores in a separate post (which contains spoilers).

Source: Reddit