In the newly rebooted Doom, players go to Hell and back (and to Hell and back again), with its metal soundtrack grinding in the background. Doom is basically 1980s album covers rendered into a video game, complete with hidden “messages” buried in the music.

YouTube user Nerd Sauce discovered the weirdness in the video above when they decided take a look at the spectrogram of the songs that make up the Doom soundtrack. The software used in the video visualizes the frequencies used in the music, turning sound into a picture. And the picture is a suitably devilish one.

Turns out, the song “Cyberdemon” on the Doom soundtrack contains some interesting images in its spectrogram: specifically, the numbers “666” and some inverted pentagrams. So just in case you were wondering, the hellishness in Doom is more than skin deep. It’s also sound deep.

Via The Verge