Ever since those four notes guided enemies down the screen in 1978’s Space Invaders, video game music has remained one of the most commonly heard sounds across the world. Yet there is a disconnect between its outsize popularity and its critical recognition. Game soundtracks rarely pad out year-end lists or are regularly reviewed in music magazines, let alone considered as credible listening options outright. The soundtrack for Ocarina of Time, the fifth edition of The Legend of Zelda—a flagship series for Nintendo that inspires such slavish devotion, both Robin Williams’ daughter and Seth Rogen’s spaniel share its name—was so full of creativity and color and wonder that it presented the most convincing possible case to argue game music belongs in the canon.

The score, composed by Nintendo’s in-house MVP Koji Kondo, was the first that truly thrived outside of its originating medium, a game centered around an ancient flute-like instrument. It quickly took on a second life as open-source material, where it was enjoyed, adapted, and shared. An entire generation grew up around the explosive popularity of the game in the late 1990s, which explains why mash-up producers feel compelled to slap Clipse over “Lost Woods,” or why countless symphonic orchestras tour their own reinterpretations, and why a genre named Zeldawave exists at all.

From the stirring opening screen to the weepy final credits, the music that flows through Ocarina of Time was a generational Rosetta Stone, encompassing Gregorian chants, Arabic scales, harp, flamenco, dark ambience, and at least one rip-off of Gustav Holst’s The Planets—an unforced and generous way to transmit those sounds into the homes of millions. In the 21 years since its release, Kondo’s score remains the one component of the game that has not dated, even as every facet of the industry has advanced by orders of magnitude. By eschewing what was or wasn’t in vogue, Kondo instead hit upon timelessness.

Koji Kondo understood the medium of video game music better than anyone. A young fan of regional jazz fusion acts Casiopea and Sadao Watanabe, as well as the grandiose prog of Emerson, Lake, and Palmer, he rolled out the Osaka School of Arts in 1984 and straight into a job at his first and only company, Nintendo. He was part of their inaugural wave of sound technicians, hired at a time when the blocky tones pumping out of arcade machines served little purpose beyond luring quarters; a ubiquitous but characterless wavelength, ripe for someone to stamp their imprint.

Although the Nintendo Entertainment System was able to play only three notes simultaneously, his score for 1985’s Super Mario Brothers was a revelation: Pixelated fish fluttered along to the rhythm of watery waltzes; the Underworld was a melody-devoid inversion of the Overworld; and you always seemed to be falling down crevices or spoing!-ing off enemy heads pleasingly in time with the music. Variables in how the game functioned were limited, which allowed Kondo to work with Nintendo’s still-small team to compose a soundtrack that existed as an invisible master hand, guiding player movement along while remaining catchy enough to be something that will be hummed or strummed along to until oceans burn.

Kondo was gifted a chance to set the parameters of a compositional practice in its infancy. Attempting to make game music diaristic was a dead end. Even Ennio Morricone’s finest film scores existed for situations that you could come across in everyday life, more or less: Binaries of love and hate, comfort and danger, hope and despair, played out with human bodies and recognizable locations. There never could be a relatable analog for Zelda’s elfin hero, Link, strafing around the belly of a whale king or being hounded by flaming skulls, so why bother? Repetition was equally a double-edged sword to master. Get it wrong, and you’re subjecting the listener to a banal ditty over and over and over. Get it right, and you’re creating something familiar to millions yet indelibly personal to the player. By the mid-’90s, Kondo was so accomplished with working through the challenges of constrained composition that the Super Nintendo’s successor, a 64-bit machine with the capacity to replicate sound significantly closer to actual music, might have seemed like letting the rest of the industry start on easy mode.

If Nintendo 64, which hit the market in the summer of 1996, broke the stratosphere of what 3D gaming could achieve with its launch title, Super Mario 64, 1998’s Ocarina of Time was the first successful attempt to stick a moon landing. Released with just 39 days left on the calendar, it still became the biggest seller of the year, besting an impressive class of ’98 that contained Metal Gear Solid, Half-Life, Banjo-Kazooie, and StarCraft. An instant hall-of-famer, Ocarina of Time improved on just about everything that came before it: immense scope, absorbing lore, dynamic storytelling, elaborate presentation—and music.

Kondo now faced an entirely new challenge to make his vision pay off. The N64’s audio fidelity and internal memory were terrible. To add embellishments to a track, you might need to bargain with coders to discreetly leave one part of the map with the uneven texture of cobblestones. Worse still, the industry was undergoing a kind of reverse automation in lockstep with upscaling technology, replacing machines and machine-capable composers for actual musicians. Compare Yasunori Mitsuda and Akira Yamaoka’s acclaimed soundtracks for 1995’s Chrono Trigger on the Super Nintendo and 2001’s Silent Hill 2 on the PlayStation 2, and the changes feel chasmic. The synthetic twinkle of the former is unmistakably tied to the 16-bit period, but the scratchy, layered textures of the latter break free from those associated tropes, and into an age of CD-quality sound design.

Initially, Kondo resisted morphing his beloved bleep-and-bloop game music into real life music. So he rebelled by keeping things unreal. He would spend days rifling through global curios in Kyoto’s record stores before merging his finds into combinations that broke with chronology, geography, and anthropology—combinations that couldn’t plausibly be found outside of a console. Vocal from as far back as 1990 about the changes sweeping through his profession, Kondo eventually embraced them, forging links to the past and casting forward imagined futures.

The sheer size of Ocarina of Time was unprecedented, which gave Kondo the freedom to let his imagination roam. As the game was being coded, he would build out his compositions from the trickle of development updates, tracing rhythms from Post-it Notes littered over his keyboard about woodland mazes and collapsing castles and Death Mountains. He waited for fitting motifs to drop into his brain, often while he was in the bath. Progress was generally fluid, nothing like the 18 months spent hacking away on 1990’s Super Mario World.

Sometimes, what was called for was pretty obvious. Glassy tones fit the “Ice Cavern,” gladiatorial horns and crashing timpani rolls gave dramatic flair to a “Boss Battle,” and a plaintive twang greets you at the “Lon Lon Ranch,” the kind of snoozy town-that-time-forgot vibe that comes off like Beck B-sides fed through a machine learning algorithm. Kondo also boldly ditched Zelda’s iconic main theme, broadly regarded as his standout work, for the very first time. This could have resulted in open revolt amongst diehards but for two majestic new pieces inserted in its place: The rousing “Hyrule Field,” which follows you throughout the game’s central area, stayed fresh by utilizing an adaptive mechanism that told the game’s internal engine to cleanly cycle between eight-bar segments with open chords, depending on whether you were in danger, resting, or in full flow on horseback. Then there’s the tender “Title Theme” greeting you as soon as the N64 loads up: drifting chords, spare keyboard rolls, one quivering ocarina, and clip-clopping hooves as Link’s horse, Epona, strides across the screen.

Other times, Kondo would need to conjure diegetic music that Link and other characters in the game respond to. Twelve of the game’s themes are based around just five notes—re, fa, la, ti and the higher-octave re—simple enough to map onto the instrument in Link’s hands, but resonant enough to occupy a permanent space in your amygdala. Concision was key; so long as your N64 was on, the loops could replay endlessly. Many of the tracks on the officially released score that accompanied Ocarina of Time landed between only 30 and 70 seconds. Striking a balance between complexity and simplicity, Kondo deepened the range of expression while keeping it elemental. “Song of Storms” is so maddeningly catchy it drives a windmill operator in the game to actual madness, ruining his life.

What was particularly arresting about Ocarina of Time was its very un-Nintendo embrace of darkness. Here was a game you brought neighborhood friends round to share, curtains drawn, watching and listening intently—not just because it was expansive and fun and un-put-downable, but because this thing was off its axis. Characters age and die, clay zombies rise up to choke you, and dungeons full of enslaved prisoners spiral like M.C. Escher paintings. All along, the music gets progressively more claustrophobic and forbidding. For once, negative space on audio tracks seemed like artistic license rather than technical limitation. When night falls, the music tapers off completely, leaving you exposed to the elements with nothing more than a bone chill for company.

Capturing this psychological turmoil in a way that connected to a broad audience pushed Kondo harder than before. The scorched earth of “Dodongo’s Cavern” is evoked through a miasmic mood piece that creeps like noxious fumes preceding a pyroclastic flow—but with Trent Reznor scoring the blockbuster first-person shooter Quake back in 1996, this sort of unsettling soundscape wasn’t exactly new. Kondo’s fascination with arcane instrumentation rarely heard in general, let alone in games, gave him the edge. An Armenian duduk snakes through the musty, grim “Spirit Temple,” marimbas pace around the climactic battle against Ganondorf—set against leaden drums in a 23/16 time signature that looks bizarre on paper, they represent the lithe movement you need to overcome a dominating but cumbersome final boss—while the rattling percussion and ephemeral hollering of “Forest Temple” respectively came from Indonesian angklung and a sample pack named Zero-G Ethnic Flavours.

Kondo’s curiosity did, however, lead to one of the larger controversies in Nintendo’s history. Rapt with excitement over an exotic chant he had likely picked up while browsing discount bins for audio travelogues, Kondo did not realize it was أَذَان (adhan), the Islamic call to prayer‎. He layered the sacred verses throughout the “Fire Temple” for atmosphere, and given the fractional Muslim population inside Japan’s cloistered society, no local testers picked it up. Corrected revisions of the game, with a more generic male choir in place, were rushed to stores as soon as the passage was caught, but stands as a lone blot on the company’s customarily sparkling copybook.

Ocarina of Time was to be Kondo’s last full soundtrack. He was responsible for most of 1999’s Majora’s Mask, drawing inspiration from Chinese opera in line with its mask-based aesthetic, but had a much-diminished role when it came to the Gaelic sea shanties of 2002’s The Wind Waker. He remains in charge of Nintendo’s music department, but as a composer, Ocarina of Time was his way of leaving it all out on a field that was in the process of being aggressively returned. Nintendo’s latter-day scores for Zelda and Mario skew more orchestral, but so do most big-budget titles now. They lack Kondo’s uncanny ability to bind feelings of happiness and sadness into an immediately nostalgic whole, so that your first listen feels like your thousandth.

A remake of Ocarina of Time in 2011 roused Kondo, like a great gatekeeper awoken by a sense of duty. He preached the necessity of continuity, giving employees strict instructions to stick as closely as possible to the original, watching out for fractional differences in tempo and timing that would ruin the malleability of the score. Tampering with the leitmotifs twinned with environments and characters was a cardinal sin: nothing could be worse than jeopardizing fond memories. Even basic SFX had to be recreated to transmit the feel of the N64 era on the handheld 3DS, despite the newer hardware being wired completely differently. Heads were scratched over a revamped “Title Theme” that Kondo kept rejecting, before his young team clocked that the N64’s characteristic reverb, used to mask the harsh compression, had been scrubbed. The opening ocarina no longer drifted into view from a far-off forest, but was front-loaded and far too clean in the mix. Once derided, the N64’s drawbacks were now cherished, imperfections to stimulate a flutter of butterflies in the gut.

One of Nintendo’s greatest strengths—or follies, depending on what stage of the deleterious decline/miraculous revival cycle the company finds itself in—is having the confidence to reach for intangible qualities of magic and the sublime in an earnest and uncynical fashion. They remain the lovable dad of the industry, corny and often eye-clawingly frustrating, but self-aware enough to make good on it. Kondo’s scores are the connective tissue in Nintendo’s enormous body of work, like Joe Hisaishi’s for Studio Ghibli films. His particular gift was to not just create music matched to gameplay, but to grasp the way sound folds itself into our surroundings, creating associations forged and never forgotten.

The central conceit of Ocarina of Time’s story is the ability to toggle between adult and kid versions of Link, warping between the bleak morass of adulthood and an era of innocence, with only flickers of the hellscape to come. This is not a luxury afforded to us in reality. Yet Nintendo do their best to bridge the divide all the same, striving to make kids feel like adults and make adults feel like kids again. No game soundtrack before or since has brought that to bear quite like Ocarina of Time, leaving an emotional response that lingers long after the system shuts down.