For those of you who have not read the book, Ready Player One’s jade key sequence has Wade Watts (played by X-Men’s Tye Sheridan in the film) act out the entirety of WarGames from memory like a movie-oriented version of karaoke.
In the Ready Player One movie, the jade key sequence throws Wade and his friends into the Overlook Hotel from The Shining and allows them to explore and exist within that ecosystem without forcing them to play out specific scenes beat-for-beat.
Per Penn, this was a way to move away from the karaoke style of the book and do something like the Arnold Schwarzenegger cult classic, Last Action Hero — a film largely predicated on the idea of outsiders entering the world of fictional films.