YouTuber Rob Scallon has seemingly done it all. The guitarist has covered plenty of Slayer and Metallica songs on banjo, made songs consisting of lyrics that people have tweeted him, and even  wrote a song without hearing a note of it. The latest challenge he got from a follower was writing a song that only went up and down in half steps. Of course, if you’re following Rob Scallon, you’re probably a musician, but if you just like riffs, it’s entirely possible you could listen to the song without knowing that it’s more of an experiment than a song, and that speaks to his talent as a musician. Check it out below.

[via Metal Sucks]