Obviously Steve.
It could only be flashbacks, unless they find a way to resurrect his character, which is not in the style of the show at all.
That theory is entirely unproven. Your claim that the Mind Flayer is "possessing" Vecna lacks any sort of evidence. If anything, season 4 leads us to believe that Vecna is controlling the Mind Flayer.
You seem to think that the Mind Flayer has a mind of its own. Everything that it did was with Vecna behind all of it. Any intention that you think it had was, in reality, Vecna all along. It is Vecna who wants to take control of the world. His goal was never to take revenge on a bunch of teenagers, but was in fact to transform the world into a new Upside Down. If his intentions had been otherwise, season 4 would have played out a lot differently.
You only ever deal with speculation. Consider what is actually in the plot of the show itself, and work your way from there.
Your theory is flawed at the source. You don't seem to understand that regardless of whether his origin is from a certain entity or not, his role in the plot is still the main antagonist. You need to examine the story itself to determine who the primary villain is, rather than trying to rationalize your faulty viewpoint through a technicality.
Doesn't change the fact that Vecna controls the Mind Flayer. Even if the Mind Flayer was his point of origin, that doesn't make it the big bad somehow.
Is the play canon?
Vecna controls both the Mind Flayer and everything else about the Upside Down, that much was made clear. It's not that complicated; the writers aren't that imaginative. If only they had the creativity of the show's fans.
It's pretty obviously Vecna. Season 4 spent a lot of time tying everything back to him in an effort to make him the main villain of the show. There isn't any other logical way to look at it.
Tough decision.
Easily the Battle of StarCourt. The best episode in season 3 by far.
No one is assigned the task of creating pages for season 5, people just do it. That's the beauty of the wiki.
Max, because Stranger Things never kills off the kids. Although obviously it was a fake death.
No quotes.
Optimusprimebumblebee "Neo Astral-X" 123 rarely knows what he's talking about.
@Michaelback The song Eddie played was Metallica's "Master of Puppets." I hope that helps.
^ I almost picked season 2 because of that.
Sources don't lie, so fair enough. I must have missed Billy's line about certain types of people. I always just assumed he was a plain old jerk to all the boys in general.
It's close between seasons 1 and 2, but I went with 1 because Hopper was the character that stuck out to me the most.
Potentially, but I don't think that was the intention behind that line when it was put in. Billy had already seen Lucas hang around Max at that point, certainly more than the other boys.
It can really only be season 1.