Mike, Joyce, Dustin, Steve, Robin, Lucas, Nancy, Will and Jonathan were all in the other world, it was nothing like the upside-down. It was just miles and miles of sand, rocks and cloves to the upside-down.

the team was about to fight Vecna but as they were getting closer to the creepy looking layer he was in.... Will got another episode. He could see though the eyes of Vecna that was after the kids in his own mind, in his own memories. This made the team freeze and Mike rushed with Joyce to Will his side.

Will was telling them everything they saw at the moment through Henry his eyes. The team had to move on for now and fight Vecna while Will tried to keep Vecna back for a little while. Joyce stayed with her son while the others went to the place vecna was hiding. They had no idea yet what was happening but the moment Robin, Mike, Steve, Dustin, Jonathan, Nancy and Lucas got close to the layer.... it started to move.

the layer... it was the Mind Flayer and Vecna had been keeping it's victims inside the body of it. The kids were in there and so was vecna himself in the middle of it. Without the kids, he couldn't collide real Hawkins with the upside-down and his world to form it into one world all together. They needed to get the kids out as soon as possible

the monster started to move, ready to attack the team yet... it seemed destracted by something, on rather.... someone else. Jane. Jane had made it to the same demention as them! She was destracting it and used her powers to attack it. Ripping it's chest open for her to enter and fight Vecna on her own.

the team had the idea to attack the Mind Flayer itself while Jane is fighting Vecna inside. Will was further away with his mother as he was using his powers to fight vecna aswell to help Jane