Earlier this month, HBO announced that Season 6 of the beloved fantasy series Game of Thrones will debut on Sunday, April 25, starting the official countdown to this highly-anticipated series' return. While the network still hasn't released a full trailer with new footage, the show's official Twitter account asked fans to tweet with the hashtags #HouseStark, #HouseTargaryen or #HouseLannister. The Twitter feed would then respond to each tweet with a brief teaser focusing on each house, which teases a number of cryptic developments.

The Game of Thrones video centering on House Lannister showcased a shredded version of the Lannister flag, with the voice of Jonathan Pryce as the High Sparrow revealing that even though they are poor with no power, the Sparrows can "overthrow an empire." The Stark family flag is also in ruins, as we hear the voice of Ramsay Bolton (Iwan Rheon) claiming that "Winterfell is mine. The Targaryen video is a bit more interesting, since it features the voice of an unknown Dothraki character, presumably speaking to Daenerys Targeryen (Emilia Clarke). He tells her that, 'You are nobody. The millionth of your name. Queen of nothing."

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At the end of Season 5, the High Sparrow manged to imprison Cersei Lannister (Lena Headey), making her walk nude through King's Landing for all to see. It remains to be seen what plans they have in store for the rest of the family, including King Tommen (Dean-Charles Chapman). As for the Bolton's, they seized control of Winterfell, but at the very end of the season, Ramsay Bolton was betrayed by Theon Greyjoy/Reek (Alfie Allen), who took Sansa Stark (Sophie Turner) and fled Winterfell. One of the last scenes of the season featured Daenerys, who had fled with her dragon Drogon, when she was surrounded by a horde of Dothraki soldiers.

Very little is known about Game of Thrones Season 6 yet, but we do know one thing for sure: George R.R. Martin's new book The Winds of Winter won't be published until after this season debuts. The author and his publishers haven't announced an exact date of publication yet, so we'll have to wait and see. Fans were left with several burning questions after Game of Thrones Season 5, most notably, the fate of Jon Snow (Kit Harington), which will surely be addressed when the show debuts in just a few months time.

Fans will be introduced to several new characters this season, including Max von Sydow as the Three-Eyed Raven, Ian McShane in an unspecified role and Pilou Asbæk, who has been rumored to be playing Euron Greyjoy, the uncle of Alfie Allen's Theon Greyjoy. Richard E. Grant and Essie Davis are portraying members of a theater troupe who are putting on a play about famous figures in Westeros, with James Faulkner, Samantha Spiro and Rebecca Benson portraying the father, mother and sister of Samwell Tarly (John Bradley). Most recently, we reported that Spartacus: Vengeance star Joseph Naufahu has come aboard, rumored to be playing a Dothraki warrior. Take a look at these new videos, and chime in with your thoughts as we wait for Game of Thrones to return.