Why can an album sound like utter shit on the first listen, but absolute genius on the second listen? Some music isn't meant to be enjoyed initially, but instead grow on you like a sacred fungus, widening your horizons and challenging your perceptions of what great music can be.

These albums may be tough to get into, but once the light-bulb moment happens, you'll wonder how you ever lived without these records in your life. From harsh noise, to atonal death metal, to who-the-fuck knows in a language that doesn't exist, here are 10 albums that are as rewarding as they are challenging.

Swans – Soundtracks for the Blind

How patient is the average music listener? Maybe they'll wait 30 seconds for a main hook or chorus before moving on to a new track? If most music fans are your typical tweens doomscrolling their way through TikTok, then Swans fans are transcendental monks on a multi-hour meditation session. Soundtracks for the Blind is almost two-and-a-half hours of textural samples and post-rock experimentation, and when you lock into it, the album will transport you to an absolutely unforgettable aural space. 

Crotchduster – Big Fat Box of Shit

This entry is challenging for how unbelievably stupid it is, but fuck… it's one of the most fun listens in metal history. From the deranged mind of Jason Suecof, Crotchduster's Big Fat Box of Shit is a collage of dick and fart jokes, sexual degeneracy and parodies of metal classics, but what makes it so rewarding is the bizarre world-building and legitimate narrative placed throughout this audio monstrosity. After a few listens, your brain will forever be engraved with the entire story of Williams, the thriving business of Mammal Sauce, and the cartoonish realm of Williamsburgland. Be warned.

Stalaggh – Projekt Misanthropia  

Called "the most terrifying album of all time," Stallagh's Projekt Misanthropia is a mysterious piece of extreme noise that's become one of metal's great urban legends. As the story goes, one artist behind Stalaggh was employed by a mental institution in Holland, and was somehow allowed to record the screams of criminally insane patients for this project. This is what you'd imagine the damnation itself to sound like, but making it through this 35-minute hellscape can be strangely satisfying. 

Magma – Mekanïk Destruktïw Kommandöh

Magma is out there. Not only is the French band one of the weirdest progressive rock projects ever, their lyrics are sung in an entirely fictional language called Kobaïan. To the average listener, the prog-opera of Magma is absolutely unlistenable, but fans will swear by Mekanïk Destruktïw Kommandöh as one of the greatest albums ever written. There's no doubt that Frank Zappa would've adored this record. 

The Dillinger Escape Plan – Calculating Infinity

An obvious choice for this list… and a rite of passage for any fan of extreme metal or mathcore. Calculating Infinity has never quite been replicated, because it sounds like a basement metalcore album played through a ‘90s desktop riddled with viruses. But after you get past the "it's just noise" phase, you'll eventually deconstruct the Dillinger Escape Plan's debut to such a degree that you'll swear it's the most genius piece of underground music ever released. Nothing like this will never happen again.

Agoraphobic Nosebleed – Altered States of America

Even for the biggest grindcore fan, 100 songs on an album is a bit much. This love-it-or-hate-it record is like being sprayed with machine gun fire while running sprints, because every 10 to 20 seconds, the listener either gets shredded by a drum machine going 300 bpm or simply gets phrases like "The Tokyo subway gassing!" screamed at them. Agoraphobic Nosebleed's Altered States of America is one of the most antisocial albums of the 2000s, but Scott Hull's obstacle course of excess can be a surprisingly satisfying endurance challenge for longtime metalheads. 

Ulcerate – Stare Into Death and Be Still

I'm including this modern death metal masterpiece as a declaration for atonal metal as a whole. Atonal music (seemingly not written in any key or mode) can be a tough hurdle to jump over due to a complete lack of functional harmony. It's not catchy, it's tough to hum along to or tap your foot to, but being absorbed into a brutal, avant-garde abyss is a penultimate metalhead experience. Albums like Gorguts' Obscura have long been bridges into this harsh subgenre, and Ulcerate's incredible Stare Into Death and Be Still will likely have the same effect for decades to come.

Portal – Swarth

This cult album from Australia's most extreme band is a masterclass of extreme dissonance. Portal's Swarth is about as close to cosmic horror as a metal album can get, and its tentacles will grab a hold of anyone open-minded enough to sit patiently with it. It's tonally filthy and grating against the ears, but it's got the hypnotic pull of a black hole. Give it a listen… because Swarth can leave the most jaded of metalheads feeling like middle schoolers who just heard Slipknot for the first time. 

Babymetal – Babymetal

Didn't expect this one, did you? Hear me out… in 2014, Babymetal issued one of the most challenging metal albums of the 2010s, not because of sonic abrasiveness or excessive runtime, but due to the extremity of its pop-idol, bubblegum cuteness. Babymetal's debut challenged the very core of the metal genre, along with every trve-pilled metalhead gatekeeper in existence. Fronted by three tween girls in tutus, Babymetal took power metal and threw it into a Hello Kitty backpack with J-pop, hip-hop, dubstep, reggae and more, creating one of the most farfetched and addictive debut albums in metal history. It was an absolute creative bullseye, and Babymetal ultimately helped pave the way for a massive cultural shift to genre-fluid music.