WARNING: This list contains spoilers for the entirety of Game of Thrones, including book spoilers.
It's clear by now that Bran Stark has a major role to play in the finale of Game of Thrones, but what exactly that role is remains a mystery. As the Three-Eyed Raven, Bran is in a unique position to influence the outcome of the war against winter. His Greenseer abilities allow him to view and even alter the past and future, and they grant him the skill to see events happening hundreds of miles away. On top of that, he is a master warg and the only person we've seen with the power to warg into another human being. With his near omnipotence and ability to control other living beings, he may just be humanity's last hope to beat back the Long Night.
Game of Thrones fans have cooked up a million different theories trying to puzzle out exactly how the series is going to end, and many of them revolve around Bran. Is he the one who will finally slay the Night King, or will he unintentionally become the thing he was supposed to fight against? It's possible that we will see Bran fly, time travel, become a White Walker, and die all in one season. We will all have to wait until April 14th to get our final clues into the Game of Thrones endgame, but these theories might give us some early hints of what is to come.
Bran Will Tell Jon About His True Heritage
Season 7 saw one of the most popular Game of Thrones fan theories, R+L=J, come true. Jon Snow's parents were Rhaegar Targaryen and Lyanna Stark, making him the rightful heir to the Iron Throne.
Together with Samwell Tarly, Bran managed to put together the whole story and reveal Jon's true identity. Jon still doesn't know about this, however, and it's likely that his younger brother (or cousin, technically) will be the one to break the news to him.
Redditor /u/mjgffect7 goes as far as to say that Bran will reveal Jon's identity by connecting him to Ned's spirit via Weirwood. Of course, Sam Tarly also knows the truth about Jon. It could be him that breaks the good news instead of Bran, so we'll have to wait and see how this one plays out.
Bran Will Dabble In Time Travel
Bran's powers of greenseeing and warging give him more power to manipulate the events of Game of Thrones than any other character, save maybe the Night King himself. He has already affected the past on two occasions, whispering to his father at the Tower of Joy and warging into Hodor when he was still a boy named Willis.
With the Army of the Dead on the march, the stakes have never been higher. It's highly likely that Bran will try and manipulate the past in order to stack the odds in favor of the living. There are a ton of different versions of this theory, including one from Redditor /u/EvilIgor that describes Bran's attempt to defeat the White Walkers using wildfire.
Bran Will Warg A Dragon
"You'll never walk again, but you will fly."
This is what the Three-Eyed Raven tells Bran the first time they meet, and it was a line that got fans instantly excited. Redditor /u/MillerTime5858 believes this bit of foreshadowing is literal, and that Bran will actually fly at some point in the future.
The most likely case for this would be Bran warging into a dragon, although he might physically ride one as well. Either way, it's a pretty solid bet that we will see this happen in some form this season, unless the Three-Eyed Raven was being purely metaphorical.
If Bran wargs into a dragon, will it be one of Dany's dragons or the Night King's dragon?
Jaime Will Sacrifice Himself To Save Bran's Life
Bran was forever paralyzed when Jaime pushed him from a tower in Winterfell, and Bran should hate him more than anyone. But the two characters have grown so much since they last saw each other that Redditor /u/or__worse__expelled thinks Jaime will go so far as to sacrifice himself for Bran.
Jaime Lannister has had one of the more transformative arcs throughout the series. He went from being a self-serving Kingslayer to one of the most noble characters on the show, but we can't forget how cruel he was in the beginning.
It would be a fitting end to his arc - one that started with him throwing a child out of a window. In a moment of chaos, likely a battle, Jaime will give his life to ensure that Bran survives. We can't be sure how their reunion will work out, or even if they'll have a reunion, but we could see something like this in the future. After all, a Lannister always pays his debts.