Heavy Song of the Week is a feature on Heavy Consequence breaking down the top metal, punk, and hard rock tracks you need to hear every Friday. This week, we highlight the new single “They Found One of My Graves” from Darkthrone. There’s a beautiful mercurial nature to Darkthrone’s music. It’s not as easy as saying that they change consistently, because they don’t; they often have long stretches of iterating on the same ideas before suddenly shifting tack. But likewise, while there is certainly a strong throughline of heavy metal in all of their music, it isn’t as simple as reducing it to that either. Take, for instance, “They Found One of My Graves,” opening track and lead single of their new album  Pre-Historic Metal . The first four minutes or so are prime post- The Underground Resistance Darkthrone, taking heavy metal from that primal place in the late ’70s and early ’80s where doom metal, progressive music, heavy rock and early speed metal hadn’t broken apart yet.…