Doom is really good – way better than anyone expected it to be. The soundtrack, too, is excellent. Back in the day, the Doom soundtrack was essentially just low-quality digital covers of popular metal riffs. These days, things are a bit more complex, but the soundtrack, just like the game, is totally horns-in-the-air metal.

It so metal, in fact, that even a visualization of the music itself reveals a hellish easter egg.

In the track “Cyberdemon,” the spectrogram visualization reveals that pentagrams and hell’s favorite number have been hidden in the track.

As the video above demonstrates, it’s pretty easy to hide whatever kind of imagery you want in a audio track, though there are limits to how detailed you can get. Artists like Aphex Twin and Nine Inch Nails have done the same. This sort of thing used to be the kind of thing worried parents whispered about along with the dangers of Dungeons & Dragons and comic books, and now it’s just a thing computers can do. It’s also a fun little detail on top of all the other fun little details that make this new Doom such a pleasant surprise.

And, as Nathan Explosion would say, it’s pretty…