Vecna is no longer the same creature we saw in Season 4. He is changed and looks more a walking piece of the Upside Down. His body looks more like a rotten tree that has holes going straight through it.
In an interview with the People, Barrie Gower, head of makeup effects team, explained why they went so heavy with CGI this time.
He went on to describe how Vecna has evolved beyond anything that looks like a human. His body is now made up of twisted vines and organic materials – less flesh and bone as he is the part of the environment itself. So to make the people see through him with holes on his chest and arm would not have been possible with makeup effects.
“Vecna evolved to the point where his body was just made up of these mutated vines and things, rather than being 100% human form,” Gower said.
Also in Season 4, Jamie Campbell Bower had to spend a significant amount of time in the makeup chair. On some days, it took as long as seven hours to get Vecna ready for filming. So with the use of CGI, they managed to complete the makeup in just three hours, making the long shooting hours more bearable for everyone involved.
Season 4 ended with Vecna battered and burned, set on fire and riddled with shotgun blasts as Hawkins pushed back against him. When asked about the new design, series co-creator Matt Duffer told Variety that Vecna needed time to recover from that beating. What emerged afterwards was not a repaired version of the old monster, but something rebuilt from the ground up.
“He more or less rebuilt his body into something stronger and hopefully cooler,” Duffer said.
