Listening to just a few minutes of Marrow Deep, Mastodon‘s tempestuous ninth album, it becomes clear quickly that they just don’t know how to feel anymore. The album is arriving roughly a year after the death of founding guitarist-vocalist Brent Hinds, whom they fired acrimoniously a few months earlier, as well as the death of drummer-vocalist Brann Dailor’s mother in February 2025. Writing an album under these circumstances wasn’t new to Mastodon.
All but a few of the group’s albums have found Atlanta-based headbangers in throes of grief: They mourned the 2018 death of manager Nick John on their most recent album, Hushed and Grim (2021), guitarist Bill Kelliher’s mom on Once More ‘Round the Sun (2014), Hinds’ brother who died in a hunting accident on The Hunter (2011), and the death by suicide of Dailor’s sister, when he was a teen, on both Crack the Skye (2009) and Remission (2002). Hinds died in a motorcycle accident about a week before the group entered the studio to record Marrow Deep.
So when vocalist-guitarist Troy Sanders growls, “We don’t get over this,” on the album’s”In the Ruins,” true pain resounds in his voice. In some ways, Marrow Deep is Mastodon’s “Shine On You Crazy Diamond,” a tribute to a bandmate who was crucial to their beginning but lost his way, as they recently explained eloquently in a video, as well as an acknowledgement of life’s frailty. When Dailor sings, “I saw your ghost again, followed by crushing feelings of regret,” to Hinds on “Ghost Again,” he sounds raw, and after a brief musical reprieve, the song congeals into the crunching, gnashing, chomping riffs that close it out. It’s heavy. It’s also weirdly emotional, at least for a metal album.
Marrow Deep bears all the sonic hallmarks of Mastodon’s discography — raspy, bellowed vocals, riffage that ranges from chunky to viscous to nubbly, off-kilter rhythms that make headbanging dangerous, and solos galore — but there’s something about the way they bring off the songs in which you can hear their turmoil. This isn’t a terrible thing. They’re playing at the peak of their abilities, and keyboardist João Nogueira and lead guitarist Nick Johnston, who each joined the group this year, keep the original trio on their toes. But their instruments often weep, howl, and ululate as much as the vocals.
“Barbarian’s Blood” opens the album with a riff that feels like drowning, as it heaves back and forth like crashing waves and Sanders cries for help, “We’re in danger, losing everything.” “Golden Spires,” one of the album’s highlights, trembles with gut-shaking rhythm guitar like the backdrop of a play tumbling down to reveal a bare stage. “Free yourself to live, all I know,” Sanders screams. “Free yourself to live.” Meanwhile, in “They’re Coming for You,” the music feels as though the world is crushing in as guitar riffs crawl like spiders before parachuting onto you, on “Out Lik a Lamb,” Nogueira’s organ swirls into a death spiral.
Although the vernacular of prog rock has been an important part of Mastodon’s sound for the past 20 years, the group’s adventurous soloing comes even more to the fore on Marrow Deep. Nogueira takes as many leads as Kelliher and Johnston, and echoes of synth- and keyboard-driven bands like Pink Floyd, Deep Purple, and even Yes are far more prominent on the album than previously. Nogueira can summon creepy, John Carpenterish analog synth (“Barbarian’s Blood,” the ballad “Moth and Bone”) and Dream Theater-like wheedling (“Snakes for Dinner”), sometimes adding to the songs (bell-like sounds in “In the Ruins”) and sometimes letting it get away from himself (closing song “The Three Fates,” which is basically a prog jam.)
The guitarists work through their feelings with bluesy motifs, pyrotechnic eruptions, and, going with the “Shine On” allusion, long, breathy, David Gilmourish phrasing. But they don’t do it all alone. As usual, Mastodon’s guest list runs deep on the album. With Converge’s Kurt Ballou co-producing it with the band and Patrik Berger (Lana Del Rey, Charli XCX), it’s no surprise Converge’s Ben Koller and Nate Newton make appearances, playing percussion and growling along, respectively. The album also features cameos by heavies from Gojira, Lamb of God, Queens of the Stone Age, and Clutch.
But it’s the intro to “The Vanishing,” played by Black Sabbath’s Geezer Butler that speaks to the overall vibe of the album, as he riffs about and jams on ideas like he’s warming up until his recitative transforms into a baleful motif. It becomes one of the album’s best songs, with an easy groove, as Dailor apes Ozzy’s vocal effect from Sabbath’s “Planet Caravan” and sings, “Watch the universe expand romantically/I see my mother join beloved sister.” Then Sanders sings words that seem to capture all of the crippling remorse he and his bandmates feel: “The more we love we suffer in it/Stays with us ’til the end.” He asks, “Can we bear the wound that never mends?” The song ends with him screaming … just screaming.
Marrow Deep at times feels turbulent, ornate, measured, chaotic, and cathartic. Most of all, it sounds mature. Gone is the callow rage and aspirations of badassery that prompted them to write Leviathan about Moby-Dick. They may try to cloak some songs with references to Greek tragedies, but the fates and furies here are Mastodon’s own, uncontrollable and unique. All you can do is listen and wonder, “How much can one band take?” as you howl along with them.
