This Saturday, the Woodlands Pavilion figures to climb fairly high in rankings for hottest place on planet Earth. Not only will it be the first, sweltering day of August — every Houstonian’s most dreaded month of summer — but none other than the mighty Slayer will have the full run of the place as the headliner of this year’s Rockstar Energy Drink Mayhem Festival, and you can bet that the hall-of-fame thrash-meisters have plans to turn the temperature up by more than a few degrees onstage.

Hey, you can’t properly pay tribute to Satan’s infernal majesty while capping off an entire day’s worth of heavy-metal bacchanalia without massive walls of flame.

“You can feel the heat from the soundboard,” says Slayer’s guitar godhead Kerry King, sounding rightly proud of the hellfire. “We prepare as best we can. When we all practice before a tour, we turn off all the A/C. Our room’s not big; it’s probably 10 ft by 15 ft. It gets warm in Southern Cal, too, although not as warm as Houston, probably. At the end of that rehearsal, when you go out and come back in, it’s like walking into a fucking locker room.”

It’s a good thing that King and crew don’t singe easily, because the annual Mayhem Festival tour grew rather more heated this year than they probably expected. Earlier this month, Mayhem Festival cofounder Kevin Lyman, who also helped found and organize the massively successful Warped Tour, pointed a few fingers at the metal scene for the struggles the fest has endured this year. The tour is smaller this year, for one thing, with fewer bands overall and fewer “headline-worthy” acts at the top.

Lyman put the blame squarely on the metal scene.

“The bands at the top all demand a certain level of fee to be on a tour,” he told the Detroit Free Press. “Unlike punk rock, metal never knows how to take a step back to move the whole scene forward…What happened was metal chased girls away because what happened was metal aged. Metal got gray, bald and fat.”

It’s hard not to read those comments as a shot taken directly at Slayer, some of the grayest, fattest and baldest guys on the tour who are definitely earning the largest fee. While King certainly has his own issues with how the tour was booked, he disagrees firmly with Lyman’s contention that the bands and fans are somehow to blame.

“I didn’t take what he said personally,” the guitarist says. “He just definitely had a mike put in front of him and said some shit that’s detrimental to this tour and any tours he has in the future — not just Mayhem, but whatever else he promotes. Because, to me, he committed business suicide.

“At the end of the day, what I think happened to Mayhem was that they waited too late in the game to get the talent they needed to pull it off correctly,” King continues. “Because what happens is, people get booked up so early these days that it seems like all the bands that could have made this more of a success are playing in Europe now instead of being on a U.S. festival. It just made the talent pool less than it could be.”

Slayer could have easily mounted their own tour this summer; Mayhem Fest certainly needs the thrash legends more than the band needs the festival. But there are certain advantages to headlining a big package, King says.

“The advantage, for me, is that if we’re doing our own tour, we’re carrying our own sound and lights, whereas if we do a big tour like this, sound and lights are provided,” he says. “It lets us invest more in the show, which is why at Mayhem you always see us with fire and video screens behind us instead of a backdrop.”

Despite his disagreements with Lyman, Kings says that he won’t close the door on future involvement with Mayhem.

“Under different circumstances, of course,” he chuckles. “One of the owners is a close friend of mine, and I can’t wait for him to come back. Not to chew him out, just to say, ‘Hey dude, I understand your partner made some shitty comments, but I don’t hold that against you. You didn’t say ‘em, you’re my bro, and somebody never should have put a mike in front of that guy. In the future you better keep a mike away from him if you want your festivals to be well-attended, because he’s just fucking everything up.’”

Whether metal has “aged” or not, Slayer will arrive in the Woodlands with some brand-new songs in tow. On September 11, the band will release its 11th studio album, Repentless — its first since the death of founding guitarist and songwriter Jeff Hanneman and the (latest) departure of original drummer Dave Lombardo. Veteran thrashers Gary Holt (Exodus) and Paul Bostaph have stepped in capably, but it will be a different Slayer on record this time out than ever before.

King says you’d be hard-pressed to know it just by listening, however.

“The only thing that was different for me was Jeff’s presence not being there,” he says. “Other than that, it was business as usual. You know, I’ve done Jeff’s tracks on records since the early ‘90s at least; so nothing is really different there. But not having his opinion was totally something I wasn’t used to.”

Much of the material for Repentless was written before Hanneman’s passing, during a period of some uncertainty for the band. King says that working on the songs helped Slayer keep some of its momentum while they monitored Hanneman’s health following a near-fatal spider bite.

“I was writing for a couple years before we tragically lost my brother,” he says. “Had I started at Jeff’s passing, it would have been a tremendous burden. When Jeff got injured with the spider-bite originally, I really dug into working on new material, because I didn’t know what was going to happen moving forward. That mindset definitely put us in a spot to succeed.”

Slayer will be out promoting Repentless through the next year, at least. King says the group has already put themselves ahead of the game by recording half a dozen songs for their next album, too, so don’t count on Slayer shuffling off into the darkness anytime soon. They may be gray, they may be bald, and they may be fat, but they are still musically potent lords of this metal domain whose rule is scarcely challenged.

“I know there are a handful of bands I like that are younger than us, but they’re certainly not carrying the torch,” King says. “The last big movement I liked was the Scandinavian movement, which had, like, Arch Enemy, the Haunted, Children of Bodom and In Flames, but those guys have been around 20 years now, so they’re no spring chickens! After that, there’s bands out there, but I don’t see anybody primed to step up as the next headliner. I don’t know why. To be sure, I don’t hear everything. Maybe they’re out there and I just don’t know it.”

And if you are out there, future headliners, please give Kevin Lyman a call.

Slayer headlines Rockstar Energy Drink Mayhem Festival on Saturday at the Woodlands Pavilion. Doors open at 1 p.m.