Eminem's music has been unrelievedly awful now for a full decade. The tenor and quality of that awfulness have varied slightly—2004's Encore was awful in an embarrassed, shrugging, transparent way; Relapse's awfulness lay in its regressive puerility. On Recovery, he discovered a new and commercially successful kind of awful, mixing the ugly viscera of domestic abuse with power-ballad glucose.

The awfulness he settled on for last year's endless Marshall Mathers LP 2 seems to be his new default: He's aggressively, thoroughly, eagerly awful, like a sociopathic A-student who thinks he's figured out exactly what you are looking for. In this case, it's snarling syllables and endless vitriol. He has never been working harder, Eminem has observed in interviews; in the sense that he's released a 78-minute album and another disc of new music all in the last year, he's right. But the wearying, dispiriting, and frankly numbing output of his current career phase isn't "work." It's maniacal persistence, of the same sort that leads some douche to text a woman 38 times about the $32k he made in June.

Seconds into the 2xCD label compilation Shady XV, which pairs 12 new songs with a disc of "greatest hits," Eminem fires up his rappity-rap sputtering chainsaw, and it never ceases for the spiritually exhausting hour that follows. Even at his peak, his rapping was never melodious, but at his nadir, he has all the musicality of a leaf-blower. The production functions simply, like a stopwatch: It's there to tell him when to start and when to stop, and occasionally a juiced-up power-rock chorus interrupts him. Submitting production to an Eminem album must feel, for a producer, something like a novelist feeding their manuscript into a wood chipper. On the one hand, you are guaranteed unprecedented exposure, and on the other, you are all but ensuring that no one will notice a note of your work.

These days, Eminem raps in a near-constant shout, with every line escalating into rage spittle that erases all tension or continuity or emotional impact. In his will to annihilate, he's also abandoned all claims to sense. "Affable guy next door's laughable/ My next whore's gonna have mechanical arms that'll jack me off with a lotion dispenser/ With a motion sensor/ No emotion, hence I guess a sick prick dies hard/ I got a Magic Johnson," he babbles on "Shady XV". He then goes onto say "I'll slap Linda Ronstadt with a lobster" and adds something about "Charles Hamilton slash Manson and Bronson (grr) animal snarls." There's nothing here to be impressed by.

Or observe this string of logorrhea from "Right For Me": "Roses are violet, mollys are blue, lost in a ball of confusion it's all an illusion/ It's probably the shrooms I'm on, cuz I think I started hallucinating/ Cuz I just thought I heard Jay Electronica and Odd Future's new shit/ And all I could do was just follow the music and end up with Paula Abdul at Lollapalooza filling water balloons with nail polish remover." Could you even read all that without your eyes glazing over?

Mathers' great talent—his 180-degree ear for how everything can be made to rhyme with everything else, how chains of these rhyming lines can be erected into dizzying towers—has officially devolved into a tic. His verses denature all sense of pronunciation and meter and natural speech rhythm; you could probably read this review as one long Eminem verse.

The glimmers of self-awareness that pop up here and there are the passing thoughts of a superstar, bobbing bottles of insight in an ocean of gibberish. "A martyr on a private charter/ Whose life could be harder?" he sneers at himself on "Shady XV". On "Fine Line", he wonders "Is it really my soul to keep, or have I sold it cheap?" Occasionally he buries a confession in plain sight, as on "Fine Line": "Sometimes I just wanna walk into Target and look at shit, browse, I don't even wanna buy nothing, I just wanna fuckin' wanna walk around inside it/ Look how excited I sound when I get to talking about life and everything about it I miss." There's nothing artful or even interesting about that phrasing, or the way he tortures and twists the vowels so they rhyme ("sometimes" finds its way mashed up against "I don't", which is forced to then rhyme with "I just", "inside it", "excited I sound" and "I miss", a mess of nonsensical emphases), but the feeling is legible, an isolation and a prevailing sense of unworthiness that has always lingered beneath Mathers' hateful snarl.

The greatest-hits disc is a misnomer: It's mostly a grab-bag of Shady throwaways and deep cuts. But there are some good songs here: Obie Trice gets three of them, all good and worth rescuing from the commercially doomed albums they were buried on. There's the Dre-produced "The Setup", from Cheers; "Cry Now [Shady Remix]"; and the Entourage theme song "Wanna Know", in which Trice spits over a tumbling garage rock sample. For some reason, several cuts from 50 Cent's Get Rich or Die Tryin', one of the most ubiquitous rap albums in history, are reproduced. There are a couple of decent, bruising Slaughterhouse songs. But the presence of these songs is mostly a signifier of the Shady Industry, the group of hangers-on that on some level seems to keep Mathers going.

On the saccharine Sia-featuring single "Guts Over Fear", Eminem baldly admits to resorting to the sophomore and puerile tactics here—threatening to punch Lana Del Rey in a BET freestyle, or threatening to rape Iggy Azalea on "Vegas"—because he has no other ideas, and nothing further to say, and is painfully aware of it: "There's no more emotion for me to pull from/ Just a bunch of playful songs that I make for fun/ So, to the break of dawn, here I go, recycling the same old song," he says. The frankness of the message is remarkable: We're stuck with him, an aging white man with nothing left to say gripping the biggest bullhorn in hip-hop.