- HBO releases new teaser trailer; first stills from upcoming season
- Grim trailer shows season 6 to be a dark one
- Fan favorites Arya Stark, Daenerys Targaryen and Tyrion Lannister set to return
Warning! The following story contains spoilers from the previous seasons of "Game of Thrones."
(CNN)Winter has come, and spring -- and more specifically April 25 -- is just around the corner.