All of the important hints dropped in 'Game of Thrones' Season 7, explained

When watching Game of Thrones, it's not a bad idea to take notes. 

The fantasy drama is one of the densest series on television — there's more to analyze in an average episode than in some college seminars. But if you've missed an important reference here or there because you were distracted by all that dragonfire, we're here to help. 

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Here are four key Easter eggs from Season 7 that may have significance in the series going forward. 

New rules for White Walkers and wights

Through the two battles in Episode 6, we discovered a new way to kill the White Walkers and their wight army. Here's what we knew before: White Walkers were created by the Children of the Forest when they pierced the heart of the Night King, formerly a human, with dragonglass. Bran saw this in a vision last season. We also knew the Night King (and potentially other White Walkers) can create more White Walkers out of living humans (recall what they did to Craster's baby). They also can create wights, which are their foot soldiers, by reanimating corpses. 

To kill a wight, the series has shown that fire (remember when Jon went up against one in Season 1?), dragonfire, dragonglass and Valyrian steel work. For a White Walker, it's just dragonglass and Valyrian steel, and maybe dragonfire. Although the Night King strolls unharmed through the flames of dragonfire on the ground during the battle, maybe a more direct hit would have been effective. 

The biggest discovery is that if you kill a White Walker, all the wights and White Walkers that he created also die. This means, as Beric pointed out, that killing the Night King (the original White Walker) will bring them all down. This changes the goals and the stakes of the war to come immeasurably. 

Gilly's discovery

In Episode 5, while Sam was too annoyed at the maesters for ignoring the threat of the White Walkers to listen to Gilly reading an old text out loud, the wilding girl revealed that Prince "Ragger," as she seemingly pronounced "Rhaegar," annulled his first marriage and remarried.

The text didn't name the women involved, but it's further evidence that Rhaegar and Lyanna Stark were in a loving, consensual relationship, upending the accepted story of Robert's Rebellion, that he rebelled to rescue Lyanna after she was kidnapped and raped by Rhaegar. It also would make Jon, whom the show heavily implied is their son, a true-born Targaryen, not a Stark bastard. It also gives him a stronger claim on the Iron Throne than his aunt, Daenerys Targaryen. 

The Valyrian Steel Knife

The dagger that an assassin used in Season 1 to attack a comatose Bran has cropped up several times this season. First, in the premiere, Sam is flipping through a text and passes by what looks like a diagram of the blade. Then Littlefinger, who in Season 1 claimed the dagger was owned by Tyrion Lannister, gives the blade to Bran. Bran then gives it to Arya, who uses it in a sparring match with Brienne that shows off the fighting styles she's learned during her journey.

It's one of the few Valyrian blades mentioned in the show, and it can kill White Walkers. Did Bran give it to Arya because he saw that she would need it in the war to come? Maybe. But if so, Arya has since left it in the possession of her sister, Sansa, after their fight in Episode 6. It was unclear if she left it permanently. 

Gendry

The reappearance of Robert Baratheon's bastard son, Gendry, was met with excitement from many Game of Thrones fans, and he quickly bonded with Jon Snow, as they believe their fathers were friends. Gendry brings a war hammer with him on the journey beyond the wall (although he hands it to Tormund when he runs back to Eastwatch), a throwback to his father, Robert, who fought with one and used it to kill Rheagar Targaryen (who it seems is Jon's real father). That could foreshadow a similar eventual confrontation between Jon and Gendry. However, Gendry, the last known descendant of a Baratheon, also could unite those houses under Jon's rule at a later date. 

A more immediate benefit of Gendry's inclusion in Jon's inner-circle is his skill as a smith. He apprenticed for a prominent blacksmith in King's Landing, noting Jon's sword right away at their meeting. Does that mean he can manipulate the ever-precious Valyrian Steel?

References to the fluidity of time 

We learned last season that Bran has the ability to travel to the past, not only to observe it, but sometimes to change it (RIP Hodor). This season has been littered with re-treads of moments and lines from earlier seasons, from Littlefinger telling Sansa, "Every possible series of events is happening all at once. Live that way and nothing will surprise you," to the Archmaester's lectures on the importance of recording history. The references may be foreshadowing another moment of the past repeating itself, or another instance where Bran changes past events.

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