If true heavy metal -- or the "extremely extreme," as its tagline reads -- is your drug of choice, Decibel magazine is your pusher, saint, savior, and thrashing guitar hero. Tied into Arch Street's Red Flag Media publishing, the monthly metal mag (with an editor-in-chief, Albert Mudrian, who has a yen for doom and black metal) has continued to preach the gospel of the hard and underground scene since 2004. Bands such as Pig Destroyer, Agoraphobic Nosebleed, Immolation, and Sleep will pledge allegiance right back at Mudrian and his mag Saturday and Sunday by playing the two-day Decibel Metal & Beer Fest at the Fillmore Philadelphia.

"The beer fest is a genius idea that I'm surprised no one had done before," says Mike Thompson of Withered.

"Decibel does a great job spreading the word for extreme metal bands that normally wouldn't get that type of exposure," says Municipal Waste's Tony Foresta. "They've helped our underground scene over the years and made it more accessible. They were supportive of us even when everyone thought we were just a ... punk band and didn't take us seriously. Plus, we made Albert hit a beer bong once. I can't really say I've done that with any other magazine editor."

That makes Wilkes-Barre native Mudrian proud, that and his desire to microscopically focus on rough metal beyond its highest-charting bands (such as Metallica). "We never had aspiration to have a circulation of 500,000 copies, before I even realized that wouldn't be a sustainable business model 13 years down the line," he says with a laugh. "Extreme metal has always been niche, so that puts Decibel at a distinct advantage, because it's smaller, specialized publications that have endured as the market for print has eroded. You've seen the fall of the general rock magazines and the welcome death of 'lifestyle publications' as advertising budgets shrink."

Fortunately for Mudrian and Decibel, they've built a devoted audience. "They trust us because we've never abandoned them," says Mudrian. "The fact that our metal fandom is authentic is a key to our success." Decibel might be niche (50,000-plus sold per issue), but its sales are solid and its reach ever-extending.

The Decibel Magazine Tour -- in its sixth year -- and Decibel Metal & Beer Fest provide opportunities to give the mag's audience something they want and to create new revenue streams beyond print. The same can be said of Decibel Books, launched in 2015 with the revised, expanded edition of Mudrian's doom-metal bible, Choosing Death, first issued in 2004. "We're driven by a simple desire to do something cool. We start with that idea, and then we figure out if it's financially viable -- never the other way around. That goes back to our authenticity."

Immolation bassist Ross Dolan knows well that Decibel is the force in the United States for exposing new people to extreme metal and its subgenres. "The magazine appeals not only to old-school fans like me, but to younger listeners looking to discover," he says. Decibel has always been a huge source of support for the death-metal scene. In addition to the magazine, the Decibel Magazine Tour takes that love and passion on the road, where Immolation shared a bill with Cannibal Corpse and Napalm Death.

"Coming from the mid- to late-'80s metal scene, where the only means of discovering bands was through fan-made black-and-white print 'zines, I love that we have a professional print magazine in an all-digital world," Dolan says with a laugh. "There's something special about having something physical to read through as opposed to sitting in front of a screen."

Ask Mudrian how his dark-metal bash merged with craft brewing (Decibel runs a monthly craft beer column, "Brewtal Truth"), and he has a ready answer: "Craft beer and extreme metal each developed because the mainstream versions of metal and beer simply were not delivering what the ardent fans of each wanted. Mötley Crüe is the Bud Light of heavy metal; it has the impact of bubblegum music and the flavor of water. Doom-, death-, and black-metal fans are always searching for something more profound. It's logical that would also apply to their taste in beer."

Withered's Thompson says that he has enjoyed Decibel's knack for embracing metal culture and for caring to shed light on what it's like for more underground bands. "The lifestyles of people like us -- beer included -- are ridiculously dynamic, but typically garner zero return on our investment. Decibel gives merit where it's due."

10 a.m.-6 p.m. Saturday and Sunday, Fillmore Philadelphia, 29 E. Allen St. Tickets: Various prices and packages. Information: thefillmorephilly.com