Mastodon guitarist Bill Kelliher spent his summer taking people to school. It’s a sweltering afternoon in Zagreb, Croatia, and Kelliher is sitting backstage before one of the final shows of a European tour.
Naturally, the master metalmaker has been crushing it on stage with the Atlanta-formed outfit, putting on a clinic while delivering an authorial blend of battering-ram rhythms, prog-spiraling licks and interstellar melodicism – hallmarks of classic albums including 2004’s Leviathan and 2009’s Crack the Skye.
Kelliher was dropping knowledge before those sets, too. All tour long he’d been knuckling into a series of one-on-one guitar lessons with fans – sometimes explaining the fundamentals, other times teaching aspiring six-stringers how to play Mastodon’s most memorable moments. Above all, he drilled in the importance of playing through your own voice, no matter whose riff it is you’re riffin’.
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“The theme of the whole lesson is this: don’t be like, ‘I’m never gonna be as good as that guy,’” he says. “I learned not to think like that a long time ago – and that rhythm is everything.”
Notably, Kelliher is saying this while seated beside current co-guitarist Nick Johnston, the Canadian virtuoso who joined last year following the departure of founding guitar hero Brent Hinds.
Nicknamed “Manimal,” Hinds’ visionary fretboard dynamism led him through countless mind-bending solos with Mastodon over the years, but he’d left the group unexpectedly in March 2025.
The ensuing months found Hinds stating that his exit was not his choice – and less than amicable; Kelliher suggested more diplomatically at the time that they’d grown apart, while this year’s The Mastodon in the Room mini-documentary adds that Hinds’ substance-abuse issues played a part in the disconnect and departure from his bandmates.
But they expected he’d eventually come back. Devastatingly, they’d never get the chance to reconnect; Hinds was killed in an August 2025 traffic accident after an SUV struck his motorcycle.
Mastodon now address the profound loss of their friend and former bandmate in Your Ghost Again, the first single from the act’s ninth album, Marrow Deep. It begins with erratically stagger-stomped brutishness, then Kelliher and Johnston team up for a dizzyingly zoetropic run. As the song cosmic-portals itself toward a melancholic, prog-tinged plane, drummer Brann Dailor and bassist Troy Sanders croon of “feelings of regret” and “visions of a future non-existent.”
While the album was written and recorded in Hinds’ absence, his presence was felt deeply within the walls of Atlanta’s West End Sound studio. Kelliher often dialed monster tones out of Hinds’ old JMP head, dubbed the “Unicorn.” The lyrics to the urgent, yet grief-stricken Snakes for Dinner further reference their late friend by name-checking Hearts Alive, a Leviathan track that featured one of Hinds’ most towering performances. While gone, Hinds is anything but forgotten.
“We weren’t expecting Brent to pass away,” Kelliher says. “We parted ways, we were moving forward, and all of a sudden that happened. So, we started reflecting on it. We couldn’t just ignore it and write some happy record. It was like, ‘This is the topic – we have to remember the good times, express it and get it off our chests.”’
Though he’s guarded on certain details, Kelliher admits Mastodon were on a “rocky road” while navigating their split from Hinds. Linking up with Johnston has helped put the veteran act back on track.
The Toronto-based Johnston first met the band members nearly a decade ago, through mutual friend and Dethklok guitarist Brendon Small. Johnston and Dailor stayed in touch, as the former carved out a body of instrumental solo work and collaborated with the likes of Paul Gilbert, Guthrie Govan, Intervals’ Aaron Marshall and Polyphia’s Tim Henson.
Johnston was putting the finishing touches on an as-yet undetailed solo album when Dailor reached out to float the idea of jamming with Mastodon. While intimidated by the prospect of joining one of his favorite bands, the Canadian six-stringer learned their set while “trying to unlock all the unique ‘isms’” of Kelliher and Hinds’ playing.
“Watching Bill work on a riff is one of the most amazing things, because he’ll sit there for hours until it’s sculpted into this perfect shape,” Johnston says, now that he’s peeked behind the curtain. “I’m not able to do that. I’m stunned at that ability. You hear that all through the music, that relentlessness.”
Mastodon played one show with YouTube shredder Ben Eller before Johnston made his onstage debut in spring 2025. He’s since clocked dozens of global appearances, including a memorable mini-set at Black Sabbath’s Back to the Beginning farewell show in Birmingham, England. That summer 2025 concert, both guitarists say, is what sealed the deal.
“It’s like he was the long-lost cousin,” Kelliher says. “He just jumped right in. I know they’re big shoes to fill, but he’s got big feet!”
Johnston ended up co-writing a few tracks on Marrow Deep. His solos run from simply-stated, yet canyon-sized bending (Your Ghost Again) to uproariously mercurial legato (Out Like a Lamb) to lysergic improvised trade-offs with keyboardist João Nogueira. Though Kelliher offered minor notes like “let’s try it a little bit more evil,” he encouraged Johnston and Nogueira to run wild and free with their playing.
![Mastodon - Steambreather [Official Music Video] - YouTube](https://img.youtube.com/vi/HEubrZV04b0/maxresdefault.jpg "“I still see Brent out of the corner of my eye sometimes. He was omnipresent in the band, on the tour bus or in the practice room”: Mastodon’s Bill Kelliher and Nick Johnston on the evolution and survival of prog-metal’s big beast 21")
Though it may be Mastodon’s first release without Hinds, the collection also surrounds the act with several lifelong friends, tourmates and studio collaborators: Queens of the Stone Age’s Josh Homme; Clutch vocalist Neil Fallon; Gojira’s Joe Duplantier; three members of hardcore band Converge (including album co-producer Kurt Ballou); and Black Sabbath’s Geezer Butler, who gets gloriously gloomy with his bass intro on The Vanishing.
From losses, to leads, to legendary guest spots, Mastodon’s current guitar tandem discuss the gratitude they’re feeling deep in their bones these days.
What was it like processing both Brent’s departure from the band and his death throughout this record?
Bill Kelliher: That’s a fairly tough question, because I don’t know if I’ve really processed it yet, you know? It was a surprise, but it wasn’t unexpected. Maybe part of me was ready for it.
You know, Brent was a wild man – one-of-a-kind, cavalier and incredible. There’s no-one like him, one of the funniest people I’ve ever met. And like [Your Ghost Again] says, I still see him out of the corner of my eye sometimes, because he was omnipresent in the band, on the tour bus or in the practice room.
Barbarian’s Blood starts the album off with heavy patterns in 7s and 4s. How did you end up leaning into that sludgy groove?
Kelliher: Most of the songs were demoed last year, but then I heard this band called Generation of Vipers. I don’t really like anything contemporary, but I’d heard them and went, “Man, I gotta go back to the drawing board; we gotta be heavier.” They shook my foundation.
On a day off in Belgium, I sat in my room and wrote three or four almost-complete songs, and that was one of them. When I played it for the guys, everyone was like, “That’s gonna make the record, that’s sick.” It’s a perfect opener. It’s definitely Mastodon… but it’s kind of left of center within our sound. And it’s tuned to A, so it’s fucking heavy.
I write weird time signatures. I can’t explain why, it just grooves to me. It did get changed, though. We took a note away, per Brann. He was like, “What if we took one note out so it grooved like this?” And it worked!
The acoustic section in Moth and Bone is one of the gentler pieces.
When Brann’s mom passed away, I was writing a lot on acoustic. I had it in this weird tuning, almost like an open G… when you hit the two high strings it gives off so much emotion
Bill Kelliher
Kelliher: When Brann’s mom passed away [in 2025], I was writing a lot on acoustic. I had it in this weird tuning, almost like an open G. It lends itself beautifully on acoustic – when you hit the two high strings it gives off so much emotion. There’s dissonance. It’s melancholy.
So I had his mom in mind, and I came up with that pattern, which was very odd. Everyone wanted to fix it and make it straight, but I was like, “No, this is the way it goes.”
Nick Johnston: Once you get that groove and rhythm with your hand, it’s this propulsion thing – but it’s not an obvious pattern. It’s just about how tight you can get all that stuff. I’m used to tracking a looser or improvised kind of playing, but this was awesome once it started to get locked in. I like the way that song ramps up, but tracking that whole heavy section was hard, with that sliding thing at the end.
Kelliher: With the dynamics, I keep thinking, “How are we going to do this live?” Am I going to have a stand with an acoustic and a double-neck that I’ll borrow from Geddy Lee?
Johnston: That would be sick! [Laughs]
Out Like a Lamb closes with two gigantic solos – one from Nick, then an organ solo from João.
Johnston: Brann and Bill had sent the song over and were like, “We need a solo as a placeholder, just to illustrate the arrangement.” That was the first take I sent over.
Kelliher: You wanted to redo it, and we were like, “No fuckin’ way are you gonna redo that.” [Laughs]. Oh my god, it’s incredible.
Johnston: I didn’t expect it to make the record because part of me was like, “I’m going to go over the top at the end, just for fun, and see what happens.”
Kelliher: It was my 55th birthday and I was on an hour-long drive to pick up some Brazilian wood [to build a table out of], and that’s when I put the whole record on for the first time after it was mastered.
When it got to that solo, it was just tears running down my face like someone was squeezing my eyeballs. I was about to go in and get the wood, but I was like, “I can’t go in there like this; I’m a mess!”
![🤘 MASTODON – Blood and Thunder LIVE | Bloodstock 2025 FESTIVAL [PRO SHOT] - YouTube](https://img.youtube.com/vi/drp79J-jG0M/maxresdefault.jpg "“I still see Brent out of the corner of my eye sometimes. He was omnipresent in the band, on the tour bus or in the practice room”: Mastodon’s Bill Kelliher and Nick Johnston on the evolution and survival of prog-metal’s big beast 25")
Nick, you adapted the set-up of your Schecter signature to play in Mastodon. What went into the build of your Silverburst Traditional?
Johnston: That was the first guitar I had done with Schecter that was just two humbuckers. I started out with all single-coils, and then I started doing HSSs and then felt this was the proper application to do two ’buckers. It’s a little hotter output.
I keep gear real simple. I usually plug right into the amp – I’m using a Bad Cat and a couple of Boss pedals to sweeten it if I need to. It’s my same guitar since the beginning; it’s just that now it’s got two humbuckers.
Do you ever drop to low A in your solo work?
Johnston: This is the first time I’ve even played in D standard.
Kelliher: You didn’t know a guitar could go that low!
Johnston: I played in E flat my whole life. Getting used to playing in these new tunings for the record – drop C and drop A – felt great.
![🎥 MASTODON – More Than I Could Chew (Live at Bloodstock 2025) [PRO SHOT] - YouTube](https://img.youtube.com/vi/3_LWBFw4kmE/maxresdefault.jpg "“I still see Brent out of the corner of my eye sometimes. He was omnipresent in the band, on the tour bus or in the practice room”: Mastodon’s Bill Kelliher and Nick Johnston on the evolution and survival of prog-metal’s big beast 26")
The finish fits the aesthetic of Bill and Troy’s instruments. Is there a story behind Mastodon’s love of the Silverburst?
Kelliher: They were so rare in the wild… but I found one when I was a kid. I remember going to [Geneseo, New York’s] Big B Buzzo’s Music and putting $50 down on a Les Paul Custom Silverburst – this was 40 years ago, and it was probably $500. I never went back to get it. I always felt so shitty that I never did.
Then one time I had a guitar stolen when we were in Houston. We pulled over to a Sam Ash or a Guitar Center and there was a used Silverburst Les Paul Custom on the wall, an ’82. It’s my favorite guitar. I still have it. That one has tons of mojo. Brent also had a Flying V Silverburst, so we both loved them. They just look fucking cool as hell!
What were you playing on this record?
Kelliher: I used a baritone ESP Viper on Barbarian’s Blood. I completely redid the guitars, because Kurt wasn’t happy with [the original tracking]. He was like, “I can hear some tuning things – let’s try this.” I ended up using that on a lot of stuff. It just sounded so big-dick-swingin’. I was like, “Woo-hoo! This thing’s great!”
I played a ’77 white Les Paul Custom. I used some ESP Sparrowhawks. And I used the ESP Ron Wood; that’s the secret weapon. I really love the sound of it, to fatten stuff up in the frequencies the humbuckers don’t pick up.
![🎥 MASTODON – Steambreather LIVE at Bloodstock 2025 [PRO SHOT Performance] - YouTube](https://img.youtube.com/vi/uiNunrBVziI/maxresdefault.jpg "“I still see Brent out of the corner of my eye sometimes. He was omnipresent in the band, on the tour bus or in the practice room”: Mastodon’s Bill Kelliher and Nick Johnston on the evolution and survival of prog-metal’s big beast 27")
What did it mean to have Geezer Butler play the intro on The Vanishing?
Kelliher: Brann orchestrated all that.
Johnston: I didn’t even know it was happening until it was basically delivered!
Kelliher: Even before Back to the Beginning, Brann got heavily back into listening to Black Sabbath. He was wearing different Sabbath T-shirts for a year straight. I was like, “Wow, he has a different Sabbath shirt on again!” [Laughs]. I think he was channeling Bill Ward.
I wrote that opening riff one day at practice, and Brann was like, “That’s fucking cool, let’s work on that!” It turned into an ode to Black Sabbath’s Planet Caravan, because we were about to do that show.
Then Brann was like, “He’s mentioned our band in his audiobook [ed. 2023’s Into the Void: From Birth to Black Sabbath – and Beyond], we’ve toured with Black Sabbath [ed. during the 2005 Ozzfest], and we were invited to do this show… would he do this?” And then Geezer was like, “Do you want it in the style of N.I.B.?”
We were beside ourselves when we heard him doing the intro, even through the cellphone. Listening to that freakin’ tone was incredible.
We were beside ourselves when we heard him doing the intro, even through the cellphone. Listening to that freakin’ tone was incredible
Bill Kelliher
Did Geezer come to Atlanta?
Kelliher: No, he did it remotely. It would have been cool if he came to our little studio, put some headphones on and did it. But that didn’t happen.
Marrow Deep reflects on the past, but likewise references a new day rising. Bill, how are you feeling about where Mastodon is positioned?
Kelliher: It’s never been better. We wouldn’t have gotten to where we are without a quarter-century of working with Brent, but I believe everything happens for a reason. Unfortunately, they’re not always the best outcomes for certain people.
