In addition to Greg Anderson and Stephen O'Malley, the album features collaborators Tos Nieuwenhuizen, Tim Midyett, Hildur Guðnadóttir, and Anthony Pateras.

Greg Anderson and Stephen O'Malley, along with frequent collaborator Tos Nieuwenhuizen, crafted Life Metal in two practice sessions in Los Angeles, California.

[1] In the studio, the band was joined by bassist Tim Midyett (Silkworm) and classically trained cellist Hildur Guðnadóttir (music department for Arrival and composer for Joker).

[2] After a Hellacopters show, guitarist Nicke Andersson explained to the band that Entombed were once described as "sellouts" by fans for signing to the major label Columbia Records in the 1990s.

[2] O'Malley and Anderson thought this was funny, and used the term to describe anything "positive or bright or happy"[3] or "not gloom-and-doom"[7] in their friend group—even knowing it was considered an insult in the Norwegian metal community.

[3] As an example of the inside joke, when Attila Csihar (Mayhem vocalist and Sunn O))) collaborator) was getting into fitness, he would say humorously, "Hey bros, I'm gonna go do some life metal.

"[7] Sunn O))) adopted the joke as the title for their album Life Metal because they felt it accurately represented "the mindset and the mood" of everyone involved in the record and the "antithesis"[3] of what was expected of the band.

[7] Life Metal was announced in February 2019 with the release of a five-minute trailer featuring a video panning across the album's artwork and part of song playing in the background.

With these public listening sessions, we hope to get a step closer to that experience of being inside the studio for you all at these special events, a few weeks before the album is unleashed upon the world.

"[14] Brayden Turrene was also positive in his appraisal of the album for Exclaim, stating that "Over the course of 20 years, the founding duo of Greg Anderson and Stephen O'Malley have redefined musicality, crafting songs of immense feeling and magnitude out of comparatively few notes.

"[15] Reviewing the album for Kerrang!, Nick Ruskell concluded, "In a weird way, Life Metal is also a superb demonstration of just how broad Sunn O)))'s palette actually is.

"[16] Jason Anderson of Uncut praised the album, writing that "Life Metal may be the richest work in the band's 21-year mission to reconfigure Tony Iommi-worthy riffage into a soundtrack for mindful meditation.

"[23] In his review for Mojo, Andrew Perry praised the album's production, writing "Albini also deserves a medal: even at moderate volume, parts of Life Metal may loosen your neighbours' guttering.

"[18] Bekki Bemrose of musicOMH gave the album 4.5 out of 5 stars, stating that "Life Metal resonates in the surrounding air particles long after the last track concludes, and will reverberate in the minds of listeners longer still.

"[19] In the review for Pitchfork, Grayson Haver Currin wrote, "These four pieces are best suited to take over a room, to fill a venue as massive as the sound itself and, in turn, to be felt.

"[20] In a less favourable review, Nick Soulsby of PopMatters said, "The biggest surprise here is that a band famed for discovering the nuances and unseen potential of repetition, finally sound repetitious.