Bethesda UK has dropped a behind-the-scenes look at the new original soundtrack for Doom Eternal. The video, featured on the Bethesda Softworks UK YouTube channel, takes a look at the composition of a heavy metal choir created specifically for the Doom Eternal OST.

Doom Eternal’s soundtrack is composed and directed by Mick Gordon. Gordon has several major titles under his belt including Doom (2016), Prey, and Wolfenstein: The New Order. For the latest game in the Doom series, Gordon and the creative staff for Eternal are looking to one-up their work from 2016.

“It’s a continuation of Doom ’16, but this really needs its own unique approach,” Gordon says in the video. The new OST will shift away from the rock-based soundtrack of the previous game towards fast-paced heavy metal OST with a focus on player engagement—oh, and a heavy metal choir.

“The big question is, right, how do you put together a heavy metal choir?” Gordon said. The answer: Gordon sent out an open casting call for heavy metal vocalists, and he was not disappointed. Vocalists for almost every heavy metal subgenre turned out to help build the choir needed for the OST. The choir was assembled at Rollins Studio Theater in Austin, Texas, to record the vocals for the soundtrack.

The choir, which Gordon called an “awesome ensemble of badasses,” was made up of equal numbers of men and women spanning numerous subgenres including death metal, trap metal, and even Mongolian metal. The goal of the Doom Eternal OST is for the music to be integrated with gameplay and the player’s actions throughout the game to create a more immersive experience.

The video was published in memory of Nature Ganganbaigal. Ganganbaigal was a member of the band Tengger Cavalry and a member of the metal choir that can be heard in the Doom Eternal soundtrack. The band had also worked on the soundtrack of Civilization VI. Nature passed in June of 2019.