One of the keys to the success of Stranger Things is how it outright revels in the 1980's. From Steven King's books (especially IT) to E.T.: The Extra-Terrestrial, The Goonies, Gremlins. Poltergeist, and seemingly everything Steven Spielberg ever touched in that decade, one could spend all day cataloging all of the myriad references and influences in Stranger Things. This isn't to say, however, the series' creators The Duffer Brothers limit themselves to the Me Decade. They have also cited Star Wars and The Dark Knight as influences to Stranger Things 2. But there's another source of influence that can be felt, if not quite directly seen, in Stranger Things 2: Game of Thrones.
The biggest show in the world has made its mark on Stranger Things 2 and the Duffer Brothers. Firstly, the production of the second season borrowed from the top secret protocols HBO and Game of Thrones' creators David Benioff and Dan Weiss utilize to keep the various plot points and details of GoT under wraps (though not always successfully). When the Duffers were producing the first season, secrecy wasn't an issue on their minds. No one had heard of their series and they had no idea it would become the monster hit on Netflix it became. Thus, security protocols like burning the sides of the scripts and utilizing codenames weren't necessary. Season 2 was a different animal altogether, requiring much tighter security to keep the new season's secrets under wraps.
Game of Thrones' influence also seems to have seeped into the creative aspects of Stranger Things 2. Nowhere is this more evident than in the story arc Eleven (Millie Bobby Brown) embarks upon this season. Eleven goes on her own private hero's journey, discovering her origins and her birth name Jane Ives, meeting her mother and her lost 'sister' Kali (Linnea Berthelsen), and then choosing to return to Hawkins, Indiana to save her friends from the Mind Flayer. There's an obvious parallel to the X-Men and Jean Grey in Eleven's story, but it also echos the life of Game of Thrones' most bad-ass teenage girl, Arya Stark (Maisie Williams).
Eleven being isolated from interacting with the rest of the main cast and then outright leaving Hawkins for a few episodes is essentially a condensed version of Arya's story from Game of Thrones season 2 through season 7. For all of those years, Arya was practically in her own show within Game of Thrones: interactions with other main cast members were fleeting, and for much of her adventures, she found herself on another continent learning to become an assassin of the Faceless Men and meeting a bunch of characters no one else in the series would meet. The same happened to Eleven when she went to Chicago and met Kali and her outcasts. Kali even served as a mentor of sorts, kind of like Eleven's own Jaqen H'ghar (Tom Wlaschiha).
Eventually, Arya also chose to reject the new faction she was recruited into - just as Eleven decided a girl didn't want to be part if Kali's life of vengeance - and wanted to return to Westeros. Ayra's original plan was to kill everyone remaining who had a hand in murder of her father Ned Stark (Sean Bean), but she eventually also returned home to her family in Winterfell and helped eliminate her family's great enemy there: Littlefinger (Aiden Gillen). Eleven wanted to go home and reunite with Mike (Finn Wolfhard) but she also knew only she could save her friends from the the Upside Down. Eleven's reward was family of her own: officially becoming the adopted daughter of Jim Hopper (David Harbour). Eleven and Arya are cut from a similar cloth: two powerful and dangerous young girls we like, sympathize with, and unabashedly root for.
Meanwhile, Will Byers (Noah Schnapp) being trapped in the Upside Down during season 1 led to his season 2 ordeal of being The Spy - possessed by the supernatural influence of the Mind Flayer and inadvertently working against his friends and family to the benefit of the evil monsters beneath Hawkins. Will essentially and unwillingly becomes the Bran Stark (Isaac Hempstead-Wright) of Stranger Things 2. Bran is the Three-Eyed Raven, the latest incarnation of an ancient magical being who can see the past of Westeros. Many Game of Thrones fans continue to theorize Bran is the cause of the evil Night King, somehow in the thrall of the Night King, or that he is the Night King himself. Will is at least fortunate he was freed from the Mind Flayer's control and has a chance at a normal life; poor Bran will never regain the use of his legs or be a normal person again. Bran is the Three-Eyed Raven forevermore.
Less overt a parallel to Game of Thrones but still bearing fleeting echoes is the relationship between two newcomers to Hawkins, Max Mayfield (Sadie Sink) and his step brother Billy Hargove (Dacre Montgomery). Billy is angry all around, especially at his lot in life of having to move to Hawkins and being forced to look out for Max, the daughter of his dad's new wife. Billy is an outright jerk to Max, and while there's no hint of Targaryen-like incest in their relationship, Billy's scary and abusive behavior towards Max has just a hint of the abuse Viserys (Harry Lloyd) heaped upon his younger sister Daenerys (Emilia Clarke) in Game of Thrones season 1. Thankfully for Max, Billy never sells her to someone, and Max's eventually getting to physically beat Billy up and take out her frustrations on him was just as satisfying as when Daenerys watched as Viserys received his 'golden crown'.
Finally, one of the most famous phrases in Game of Thrones is "Hold the Door!" - the dying sacrifice of Hodor (Kristian Nairn) to let Bran and his friends escape the White Walkers, as well as the source of his name 'Hodor'. Eleven concluded Stranger Things 2 with her own version of this: she left Kali in Chicago and returned to Hawkins to 'Seal the Gate' to the Upside Down in the bowels deep beneath the town. Things definitely worked out better for Eleven than they did for Hodor.