𝐞𝐥𝐬𝐢𝐞

In S1 he wears his iconic jacket with the giant red collar that evokes a Demogorgon's maw. For now, this is an innocent choice that simply serves as foreshadowing for the horrors to come.

During his S2 possession, he wears only grey, blue (symbolizing Mike perhaps?) and Vecna's signature red. But interestingly, the more control Vecna has over Will, the less red is present in his outfits. I can see two ways of looking at this, both of which are probably true:

It symbolizes his loss of individuality: S1 showed us that he likes wearing red, after all, and he wears it prominently in 2x01 as well. His efforts to reclaim the boy he was before his kidnapping aren't working.

It symbolizes how agreeable he is about having Vecna in his head: some red stripes remain on his pyjama bottoms while he still has enough control to spy on Vecna, but it's gone by the time Vecna starts using him as a spy in turn.

S3 begins with Will still only wearing blue and grey... but the red is back.

Vecna's back too, of course, but it's worth noting that this season brings with it the onset of puberty and the obnoxious reality that is Mike Wheeler spending all his time with El Hopper -- perhaps Will's anger about that can't help but splash onto his outfits.

Either way, red never appears on his neck (the area which most strongly symbolizes his connection to Vecna) until he fights with Mike and destroys Castle Byers -- after which his collar turns solid red and stays that way for the rest of the season.

(If you were skeptical about red symbolizing how agreeable Will is about having Vecna in his head before, maybe now it's making a bit more sense -- he spends this portion of the season choosing to be a glorified Geiger counter for the party.)

Red continues to dominate his wardrobe after the gate is closed, but it's gone from his neck. At least, his collar is blue when he affirms his devotion to Mike in the S3 epilogue:

It doesn't stay that way, though. After six months in Lenora with no contact from Mike, the collar is red again. Will can't sense Vecna here, but he certainly can sense how lonely and different he is.

(And just because Vecna isn't literally in his head doesn't mean he isn't on his mind. It's probably not a coincidence that the flirty girl is a Patty Newby lookalike who just so happens to share a shot with the word "HENRY" appearing behind Will's neck. He relates to Henry way more than he's letting on, I think.)

The instant Mike returns to him, he immediately excises almost all red from his wardrobe -- just swinging directly from one extreme to the other, with emphasis on blues and greys at first followed by generic Byers earth tones for the rest of the season.

I don't think this is a promising sign. The only other time red was this absent from his wardrobe was when Vecna was crushing all the individuality out of him -- and now he's doing it to himself.

Anyway, then S5 happens.

Byler Week Day 3: Birthdaygate/Byler gates

i am choosing to believe that Vecna made everyone forget Will's birthday for Plot Reasons (do I know what plot reasons? absolutely not) and that will eventually be resolved, so imagine this is in the aftermath of that 👍