Twenty years ago, Dave Grohl accomplished something that once seemed impossible: He stepped out of Kurt Cobain’s shadow. At this point we all know Grohl as rock ‘n’ roll’s friendly worldwide ambassador, the dude from a zillion music documentaries and awards show all-star bands, the longhaired living embodiment of R-A-W-K rawk. He’s got a long discography of Foo Fighters albums behind him now and is undeniably one of the biggest rock stars in the world. He’s a legacy artist trading off nobody’s legacy but his own.

That legacy began to solidify with The Colour And The Shape, Foo Fighters’ second album, which turns 20 years old this Saturday. It is the band’s bestselling album, arguably their best-loved, and maybe even their best, period — though the Foos’ self-titled debut album from two years before is a monster in its own right and deserves to be in that conversation. Weezer, one of the only other ’90s alt-rock titans still standing, are a relevant parallel here: As with the first two Weezer albums, both of those first two Foo Fighters albums are stacked (to the rafters, you might say). Like those early Weezer records, the first two Foos LPs present distinct, competing visions of the band, both so excellent that either one could be my personal favorite depending on the day. And like Weezer, the Foos never quite recaptured that initial magic again, despite delivering a number of great singles in the ensuing decades.

Here’s where the Weezer comparison breaks down: Rivers Cuomo and company began with a slick set of pop songs and followed it up with the noisier and more unhinged Pinkerton, whereas Grohl’s band followed the opposite trajectory. Foo Fighters presented a scrappier and more fuzzed-out vision of the band; it was a collection of demos Grohl had been working on while still drumming for Nirvana, and that band’s rangy aggression left its mark on the first batch of Foo Fighters songs more than it ever would again. Their debut made them mainstays on MTV and rock radio, but it didn’t help them shake their public perception as a Nirvana side project.

With The Colour And The Shape, Foo Fighters asserted their identity as a band of their own, partially because in the interim between albums they actually became a band rather than a Grohl solo project, with the Germs’ Pat Smear on guitar and Sunny Day Real Estate’s Nate Mendel on bass. (SDRE’s drummer William Goldsmith initially contributed to the sessions, but Grohl — arguably the greatest rock drummer in history — ended up re-doing all his drum takes, causing Goldsmith to quit and clearing the way for permanent Foos drummer Taylor Hawkins to join the fold.) They also teamed with a hotshot producer for the first time, employing Pixies studio guru Gil Norton to make their music gleam.

Most importantly, they started to sound more like a band of their own. Colour crystallized the sound that would become the Foo Fighters standard, less grungy and more poppy without losing its arena-rock heft, a fertile midpoint between Grohl’s considerable pop instincts and his shrieking hardcore roots. And it ventured beyond that template too, successfully toying with all sorts of other styles while maintaining Grohl’s emerging voice. Perhaps Grohl noticed the jangly pop tune “Big Me,” an outlier on the first Foos record, had become its biggest hit, or maybe the success of the first album encouraged him to realize the full scope of his ambitions. Whatever the reason, The Colour And The Shape significantly broadened this band’s horizons: One three-song stretch offers a shuffling acoustic ditty (“See You”), a screaming Pixies sendup (“Enough Space”), and a gargantuan power ballad (“February Stars”). More lightweight forms of balladry manifest on lo-fi lullaby “Doll,” dreamy slowdance “Walking After You,” and “Up In Arms,” which eventually blooms into a power-pop burner.

The album’s greatest highlights, though, are the ones that drench Grohl’s melodic instincts in rocket fuel. After “Doll,” a prologue of sorts, the album’s opening run features a stunning sequence of power-pop gems. It begins with the furious “Monkey Wrench,” a song so tightly constructed that it seems to clench with more and more tension until it snaps. From there we get the dynamic “Hey, Johnny Park!” and the pulsing, pounding “My Poor Brain.” We get “Wind Up,” on which that old Nirvana sound resurfaces only to be upended by one of Grohl’s unmistakably catchy choruses. We get “Up In Arms,” a drowsy retro exercise that wakes up in a big way halfway through. And we get “My Hero,” a true alt-rock classic boasting some of Foo Fighters’ most memorable guitar and drum work, a hook for the ages, and emotional firepower befitting a tribute to Grohl’s late, great bandmate Cobain (even if Grohl has said it’s about “solid everyday people — people you can rely on”).

Add it all up and you’d have a tremendous album even without factoring in “Everlong,” the anthem of anthems, the pinnacle of Grohl’s songwriting career. But “Everlong,” inspired by Grohl’s passionate connection to Veruca Salt’s Louise Post in the aftermath of his marriage to Jennifer Youngblood, is there too, thank God. From its pantheon-level guitar riffs to its expertly escalating drama to its iconic Michel Gondry-directed music video — a surreal Evil Dead/Sid And Nancy parody in which Grohl’s hand periodically enlarges to comic extremes to slap his foes across the face — “Everlong” endures as not just Foo Fighters’ signature song but one of the greatest songs in rock history. Last month SPIN’s Jeremy Gordon wrote that he likes it better than any Nirvana song, which might be crazy but also speaks to the track’s legendary status among those of us who grew up loving the Foo Fighters. It’s glorious, and there’s nothing else quite like it in Grohl’s discography.

You could say that about The Colour And The Shape at large. Foo Fighters never delivered such a complete album-length statement again, settling instead into a role as consistent rock hitmakers in an era when rock hitmakers were becoming less and less common. That persistence has helped to elevate this album’s standing retrospectively, from one of many fascinating documents of the late alternative era to the most important album by one of modern rock’s most popular bands. But even if Foo Fighters hadn’t lasted, I imagine we’d still be looking back on The Colour And The Shape as a landmark release — a legacy Grohl can be proud to call his own.