Warning: contains SPOILERS for the Stranger Things season 4 finale «The Piggyback.»
All of Max's memories in the Stranger Things season 4 finale «The Piggyback» have their own significance and purpose to them. Max Mayfield (Sadie Sink) becomes one of Vecna's (Jamie Campbell Bower) primary targets due to her trauma relating to her brother's season 3 death. After Max escapes Vecna's clutches in Stranger Things season 4, episode 4 «Dear Billy,» Vecna becomes even more ruthless in his pursuit. Likewise, with Max understanding Vecna's killing methods more, she develops her own tactics in protecting herself.
Max arms herself from «Dear Billy» onward with a headset playing Kate Bush's «Running Up That Hill» after the power of music against Vecna is discovered. Of course, Max realizes that music alone doesn't deter Stranger Things' Vecna, as it's not the song but the happy memories that the song elicits that save her. With Max being used as bait for the Vecna attack, Max knows she has to put «Running Up That Hill» away at some point. In turn, she takes herself to her happiest memory as a foolproof defense mechanism. Vecna, unfortunately, catches onto this plan and uses it against her by manipulating her memories.
Related: Explaining Vecna's Entire Plan & Its Massive Impact On Stranger Things
Throughout «The Piggyback,» a psychic memory battle involving Max, Vecna, and Eleven (Millie Bobby Brown) ensues. Max's memories not only provide character development, as flashbacks often do, but they're also used as weapons and defense shields. With Max subverting a Stranger Things season 4 death as a result of her and Eleven's teamwork against Vecna, these memories not only become insightful but lifesaving — albeit, barely.
Read more on screenrant.com