Some bands just love to show off, Californian sludgsters Intronaut being a perfect example. This is their sixth full-length and the essential formula of Neurosis-esque sludge plus jazz and prog hasn't gotten old by any means, although it has shifted more in favour of the prog than the sludge. Still, the band are instrumentally sound and have more than capable songwriting skills, all adding up to make Fluid Existential Inversions a frantic, fun time. MVP has to go to session drummer Alex Rüdinger (Conquering Dystopia, ex-The Faceless), providing a terrific and multi-faceted battery that more than enhances workouts like Cubensis. All involved acquit themselves well, however, guitarists and vocalists Sacha Dunable and Dave Timnick keeping the action moving with interesting, often downright psychedelic guitar work as well as more djent-y violence (The Cull, for instance) and even making brief intro Procurement of the Victuals interesting thanks to those weird, high-pitched riffs.

Their vocal contributions are more important than you might think for such an instrumental-focused group, too; not quite perfect clean singers, admittedly, but having a grungy charm of their own and definitely adding flourishes to already killer pieces like Contrapasso. And like the best out there they know when to shut up and let the instruments do the talking, which is a sadly underrated skill in heavy music! That's not at all to forget about bassist Joe Lester, who is in many ways the foundation of the crazy structures built by his bandmates; the eerie, futuristic Speaking of Orbs a great showcase for him especially before the track builds to something between early Cynic and some of the more experimental metalcore groups before some nicely old-school Mastodonic riff-attacks roll in.

You can tell the band love metal as much as their more esoteric influences from heavy moments like this, of which there are plenty; the riff-driven intro to the following Tripolar another example, the metal assault and Pink Floyd-y spacey interlude given equal importance. Overall, however, it's all about the drums, Check Your Misfortune's heavier tone (in both riffs and vocals) and lighter and proggier interlude both driven by Rüdinger's playing. Even the more typically sludgy rumble of Pangloss has a technical precision closer in spirit to the Meshuggahs of the world than the more usual sludge suspects, entirely aided by that inhuman drumming. By the time seven-minute finale Sour Everythings rolls around, it's hard not to be a little overwhelmed by the sheer relentlessness of it all; fifty minutes of this sort of music is a lot. Yet there's nothing specific that needs cutting from Fluid Existential Inversions, which lives up to the rich flamboyance of its title by being, well, a rich and flamboyant album, with plenty of meat as well as fat on the bone!