At 6:30 four musicians stood on stage squinting. It wasn't yellow stage lights that blinded them, but rather the early evening sun streaming in through the venue's west-facing windows. It was a lovely day – sunny, warm, blue skies – just the sort of day ill-suited for extreme metal.

Those blinded victims were Vale of Pnath – a quartet from Denver featuring vocalist Ken Sorceron, guitarists Vance Valenzuela and Greg Paulson, and drummer Gabe Seeber. It's possible that a bassist started the tour but was sacrificed and eaten by the headliner. And while that's sad for his family, thankfully his passing didn't impact the guitar riffs that define the act's current melodic death metal. Sure, Sorceron made his case – he paced the stage screaming his throaty vocals, held one scream astonishingly long, and appeared every bit of the impressive Viking that he is, but it was the riffs that prevailed. After the first number he shouted, "Let me see your horns!" and he got a few, but the bright room was still filling in. It wasn't yet time for devil horns or banter – just riffs. Pre-recorded musical elements generally filled the space between songs, adding in the atmospheric elements found on the act's recordings. Those backing tracks also provided the necessary acoustic introductions. The leads and riffs were live. Those hoping for blackened tremolo picking were occasionally rewarded, while those looking for the band's earlier technical death elements may have been disappointed. Seeber's drums sounded good with no annoying audible triggers and honest double bass footwork. Was he even playing to a click track? Surely he was, but his style seemed more organic than bulletproof. It was for the better in my opinion, as it provided the perfect mid-tempo headbanging cadence for a bed of riffs. Riffs riffs riffs.

The stage was turned over quickly, the music on PA faded, and the next act's intro music began. For ten minutes throat singers, acoustic drones, and guttural chanting established the necessary atmosphere. At 7:20 Russia's Arkona took the stage represented by Maria Arkhipova (vocals), Sergei Atrashkevich (guitar), Ruslan Oganyan (bass), and Aleksandr Smirnov (drums). The musicians were adorned in robes, cloaks, and tunics reminiscent of the early medieval period when Slavic paganism came under attack from Christianity. This era serves not only as the group's lyrical inspiration, but also as its identity. Despite the pre-show music and period-appropriate togs, the room was not fully transformed into a dark night on the Eurasian Steppe – the setting Midwestern sun still illuminated the lower half of each performer and warmed my back as I snapped photos of Arkhipova. She was a delight to watch and a challenge to capture. Her movements were entrancing as she flowed back and forth, dancing all her limbs independently. When she stood still her arms contorted and reached heavenward resembling a gnarled juniper. Several times she collapsed to the floor, nearly disappearing into her robes. Her vocals were even more impressive, moving from ethereal and clean to impressively low and animalistic. Around her the band delivered blackened folk metal rich in tremolo and frequently driven by surging blast beats and crashing cymbals. Despite the band's deep interest in the Middle Ages, Smirnov was surrounded by drum triggers and iPads that managed backing tracks consisting of folk instruments, keys, and more. Numbers like "Goi, Rode, Goi!" would have been incomplete without the layers of pre-recorded balalaikas, domras, bagpipes, choirs and more that joined the song's driving metal. Folk took an even bigger role in closer "Zimushka." In the finale, the metal layers were entirely stripped away, showcasing folk melodies and culminating in a ceremonial and ritualistic a cappella finale. The two hundred fans at the show were blessed by Arkona's amazing presence.

While I had come for Arkona, it was soon obvious that the act had only set the stage for the headliner. Eerie pre-show music played for a full half hour. It filled the room with the sound of rattling chains while actual chains were brought up to adorn the stage. A parade of enormous, inverted crucifixes decorated with animal skulls followed. Finally, techs placed bubbling goblets of dry ice to complete the look – as if they were staging a home for sale on HGTV (Hell and Gorgon television?). With every accoutrement, the audience grew ever more anxious, packing closer to the stage as every minute passed. Then Austria's Belphegor appeared. Vocalist/guitarist Helmuth Lehner stood center stage, lit by a bright white light from below ensuring the blood that dripped from his eyes over his white corpse paint was visible. He was flanked by a bassist (probably long-time collaborator Serpenth) and a second guitarist (the group has employed a number of different touring rhythm guitarists). Both remained in the shadows figuratively and literally. The similarly unnamed drummer was barely visible at the back of the stage, placed high on a riser, but obscured by towering drum racks. After thirty-five years of activity, Lehner remains the only original member, steering the project as he sees fit. While that has always meant a focus on blackened death, throughout the years he's shifted the band from raw and brutal, to technical precision, to the current focus on atmosphere. His voice has grown accordingly employing growls, shrieks, guttural grunts, spoken interludes and chants, and more. Each style was fueled by a bottle of Jack Daniels that Lehner and his cohorts passed around during the set. Between numbers Lehner shouted "Kansas City" inciting the easily excitable audience. A handful of them kept a push pit open throughout the night.

At the edge of the stage I felt the chaos of the performance. I was forced to dodge the dancers and compose my photos amidst arms stretched out in the infernal salute. There was no barricade separating the performers from the audience. It was exhilarating and exhausting. When I tucked my camera into its bag and moved to the back of the room, I discovered additional nuance. Suddenly the backing tracks revealed organs and acoustic guitars that added depth to the compositions. The sublime melody of 2008's "Stigma Diabolicum" rose from the din. After eleven songs the musicians slipped backstage, just out of sight of the room.

By now the crowd was exhausted. There were a few enthusiastic calls for an encore, but most conserved their energy, knowing the band would return regardless. When the inevitable happened, the quartet chose to close with "Gasmask Terror." It's an apocalyptic tale of nuclear and chemical annihilation with big drums and bigger riffs. From the lyrics it's unclear which side Lehner is on, only that he revels in the destruction. The concert may have started under inappropriately sunny skies, but Belphegor ensured it ended in a fittingly dark place.