Game Of Thrones: Season 6 - 7 Clues From "Blood Of My Blood" Trailer
6. The White Walkers Are Still Coming
Despite Summer, Leaf AND Hodor all dying to try and keep them at bay it seems that stemming a tide of white walkers is as impossible as changing a river's flow, because the next episode will see them still on the trail of Bran and Meera.
And given the fact that Meera can't exactly pull Bran very quickly, you can't see anything but disaster upcoming. One brief shot in the teaser actually shows Meera taking up a stone as a weapon, presumably after finding cover. Because a stone is going to do lots of damage...
So there's going to be a breaking point. My money is on Meera leaving Bran to escape after being unable to rouse him, and then him either coming into contact with the Night's King who decides he needs him, OR somehow warging into some of the white walkers to fight the others off.
Now that would be a spectacle for the opening act of the episode.