Hold on to your tunics! Game of Thrones is back and bloodier than ever.

We already know that HBO's fantasy drama returns this season with major changes from the original book series by George R.R. Martin that includes deaths for characters who are still alive in the novels. In fact, one of those deaths will be a major player and will take place in the very first episode back. This therefore eradicates this character's entire remaining story line, which was not inconsequential in the books.

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But the surprises are just beginning. One face we certainly didn't expect to return is Jaqen H'ghar (Tom Wlaschiha), the mysterious Braavosi who killed three men for Arya (Maisie Williams), gave her a coin and then changed his appearance in the blink of an eye. If anything, we thought we'd see the return of the actor who was Jaqen's new face.

"That's really tricky. I thought, 'Maybe I will be back, but not with my face,'" Wlaschiha tells TVGuide.com. "I was totally surprised. I'd always hoped to be back at some point, but with Game of Thrones you can never be sure," he says. "I think at some point in the season, [Jaqen and Arya] will meet."

Martin himself weighs in on how major the changes could be and even drops a hint that one existing character could take part in a pivotal plot point that they never had a part of in the books. The author says, "As far back as Season 1 when people asked me about the adaptation, I talked about the butterfly effect... Some of these changes may seem very small, like stepping on a butterfly, but when you drop a character from Season 1, then when that character becomes crucially important in Season 5, you don't have that character because that character has never been present. So then you have to make a bigger change and then possibly a much bigger change than that."

And while fans of the books chew on that, Martin speculates on the endgame of showrunners David Benioff and D.B. Weiss for the series versus his own. "I think their endgame will be the same in broad strokes, but it will be very different in an enormous amount of detail," he says. "We've discussed the ultimate ending of the book and the fate of many of the major characters. But as you know, there are many, many secondary characters, tertiary characters. I haven't sat down with David and Dan and done a list of the top 150 characters and what's going to happen to them in [the] books, so in some cases, the fates are going to be quite different."

Who do you think is going to die in the premiere? In what capacity will Jaqen return? Who will have to step up their game this season to make up for a missing character? Share your theories below (and please indicate spoilers for non-book readers.)

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