Warning: this article contains SPOILERS for Stranger Things season 4

Jamie Campbell Bower reveals his favorite thing about performing as Vecna in Stranger Things season 4. The most recent season of Stranger Things quickly became Netflix’s most-watched English language show. Season 4 picks up a few months after the intense season 3 finale and follows Eleven (Millie Bobby Brown) living with the Byers family, as they each struggle to settle into their new lives outside of Hawkins, Indiana. Even though Eleven has lost her powers, the otherworldly problems don’t stop, as audiences are finally given some answers about what the Upside Down is and how it came to be.

Season 4 introduced several new characters like Chrissy, Eddie, and Argyle, as well as putting a name and face to the one controlling the Upside Down. Dubbed Vecna, this new villain enters troubled minds and kills his victims from the inside out. In the season 4 volume 1 finale, it’s revealed that Vecna is One from Hawkins Lab, transformed by the Upside Down after his confrontation with a young Eleven. Following his banishment to the Upside Down, Vecna’s appearance becomes entirely unrecognizable from One’s, taking inspiration from Game of Thrones’ Night King.

Related: Explaining Vecna's Entire Plan & Its Massive Impact On Stranger Things

Following the release of Stranger Things season 4 volume 2, Bower sat down with Screen Rant to discuss his role as Vecna. During this interview, the actor shares some of his favorite things to do on set. Though his Vecna makeup would make it easy, Bower didn’t set out to scare his co-workers, instead enjoying some time to himself after the lengthy application process. He reveals that he loves getting to use his Vecna voice and after a long day the actor would utilize his monstrous voice for some out-of-character phrases. Read his full quote below:

I try not to mess with people too much. After I would have the application put on, I would go back to my trailer, sit there, and just take about half an hour just to reset. I loved talking in the voice. That was always my favorite thing, talking in the voice. So, at the end of a long day, the things that were coming out of my mouth in the Vecna voice were always very interesting and very funny. But, I really like just skulking around and being grim.

jamie campbell bower and millie bobby brown as one and eleven playing chess in stranger things season 4

Vecna’s petrifying appearance is well-suited to the horror of Stranger Things season 4. He is widely considered one of the show's most frightening villains, with an incredible power that rivals Eleven at her strongest. Though it wasn’t just audiences that were scared of the latest Stranger Things creature. While filming Vecna and Eleven’s battle in Max’s mind, Brown’s terror was very real. Bower revealed that his co-star was disgusted by his newly horrifying appearance, bursting into tears upon seeing Vecna and refusing to look at him.

Unlike the monsters of previous seasons, Vecna is mostly created through practical effect. Though reports vary, it’s said to take between a staggering six to eight-and-a-half hours for Bower's Vecna costume and makeup to be fully applied. Even though the makeup isn’t necessarily needed for Bower’s Vecna voice outside of Stranger Things, it certainly adds to the intensity of it.

Next: How Old Is Vecna (& Henry Creel) In Stranger Things?