Michael Deeds: Photos, videos of Slayer, King Diamond at Mayhem Festival

With temperatures topping 100 degrees, it might seem like the devil has been visiting the Treasure Valley for the past several days. But things got real demonic for heavy metal fans Wednesday at the Ford Idaho Center Amphitheater in Nampa.

Satanic imagery-loving icons Slayer and King Diamond headlined the multi-band Mayhem Festival, which attracted about 4,000 sweating fans. That’s less than half of what this tour used to draw, partly because heavy metal is aging out as a genre.

Slayer and King Diamond rose to fame in the 1980s. These acts are growing older. But ... wow. Neither has slowed down. Even in summer heat that resembled hell.

King Diamond — Lucifer’s official poster boy — is a love or hate experience. (I loved it.) Influenced heavily by the theatrics of Alice Cooper, the Danish-born singer uncorked his operatic falsetto while prancing around the stage enthusiastically. Say what you will about his vocal style; Diamond, 59, still hits those high notes perfectly. (A deal with the devil, perhaps? By the way, the decades-younger backing vocalist was his wife.) Longtime guitarist Andy LaRocque occasionally looked like he was a few degrees away from sunstroke. But the Swede still shredded effortlessly on his ax. Bottom line: Terrific set. I kept thinking that Idaho Shakespeare Festival would appreciate King Diamond’s act. I mean, come on: A woman giving birth on stage to a fake baby?

Although Slayer only has two of its original four members, the group still crushes in concert. With the ferocity of a rabid animal, Slayer tore through song after tightly executed song. Frontman Tom Araya doesn’t go for those upper-register screams as much anymore, but he’s still formidable and convincing. And Kerry King, who pummels rather than plays guitar, headbanged non-stop like some sort of Evil Energizer Bunny. Blast-furnace-like pyrotechnics — including wicked, upside-down crosses created by flames — added to the sensory carnage. Sla-yer! Sla-yer! (Sorry, Mom.)

Remember: If it’s too loud, you’re too old.

This story was originally published July 2, 2015 at 3:05 PM with the headline "Michael Deeds: Photos, videos of Slayer, King Diamond at Mayhem Festival."