User blog comment:Jimeee/Bethesda tweets mysterious teaser picture.../@comment-4502503-20121103034021

Personally it looks like a Snow Elf to me. If you compare the Falmer Helmet with the Mask in this picture it's easy to see the similarities in design, and shape. Going off the gold color I'm assuming it is a highranking Snow Elf. Possibly another Snow Prince. This leads me to believe that the dlc is about how the Snow Elves have made a return as predicted by Gelebor, but they have retured to take vengance on their most hated enemies: The Nords. And that they have occupied Solstheim (the place of their most devastating defeat) to launch an attack on Skyrim.