Game of Thrones teasers each have a title to help define their theme, even when those clips don't have any actual footage of the upcoming season. For instance, the sigil filled teaser revealing the show would return in April 2019 was entitled "Dragonstone." Last year's teaser involving Cersei, Jon Snow, and Daenerys traversing through the halls of King's Landing was entitled "The Long Walk." The latest Game of Thrones trailer is called "Crypts of Winterfell." What is the crypt of Winterfell? The show (and the books) have returned to this space again and again.
While fans have spent countless hours all over Westeros, from King's Landing to the Wall, the heart of the series has always been Winterfell. It's where the Starks have resided since the Age of Heroes. It was constructed by legendary Bran the Builder, and supposedly, there should always be a Stark living within it for all the remain right with the world.
The crypts are a labyrinth maze beneath the keep, where generations of Starks have been laid to rest. In the books, it is also described as a place of safety, where persecuted Starks hid out, sometimes for years. (It's also how Bran and Rickon escape Theon during Season 2's takeover.)
In the books, the statues of the Kings of Winter are said to always be carved with a longsword laying across their laps, in case the vault needs defending. (The show doesn't bother with this detail.) It's notable though having statues made of the deceased used to only be for the lords of the manor. The tradition of having figures for all family members made started in Ned's generation.
Those statues of Ned's generation are a curious choice. Ned is nothing if not wedding to honor and tradition. And yet it was he who chose to break tradition and make likenesses of his brother, Brandon (killed by the Mad King) and his sister Lyanna, suggesting Ned felt like he owed them a debt of some sort, a kind of survivor's guilt. He may have lived to be lord, but they were the real heroes.
The idea there was guilt involved also comes up when Sansa visits the crypts to honor her ancestors in a private ceremony before she marries Ramsay Bolton.
Sansa, in a lot of ways, takes after her father when it comes to Stark traditions. But even she admits to Littlefinger she doesn't know a lot about her dead relatives, or even her father's connection to them. Sometimes she would just find him down here lighting a candle to Lyanna for reasons she could not name.
The show's highlighting of the crypts heading into the final season is most likely because this is the place Ned buried the history of his family. But it also represents a place of safety. This could be where the Starks make their stand against the Night King, with the Kings of Winter at their sides.
Will Jon find proof of his ancestry by visiting Lyanna's grave? Are the crypts key to defeating the Night King? Game of Thrones Season 8 returns with answers on April 14, 2019.