Circa 1987, a small Japanese software company called Square decided to make one last video game. On the verge of bankruptcy, it believed its time was almost up so named it with that in mind: Final Fantasy.

Fast-forward 30 years and the board at what is now Square-Enix likely erupts into laughter when recalling the story over Friday drinks. Final Fantasy has become the company’s longest-running and most revered creation, a series so beloved that even its music has transcended the game as a standalone force of nostalgia.

It’s been six years since the Distant Worlds philharmonic orchestra (and chorus) last came to Australia, and the Sydney show at the International Convention Centre marks its first stop on a worldwide tour, which will take in south-east Asia, Europe and its native United States where, in 2005, it became the first ensemble to showcase the music of Final Fantasy outside Japan.

Judging by the near-capacity venue, what should be a niche interest – a live orchestral performance of arrangements from Japanese role-playing games dating back to the 80s – has become a cult of weirdly wonderful devotion.

A black mage, a white mage and a red mage amble by in a single file of cosplay, dressed as Final Fantasy’s elaborately clothed spellcasters. They take their seats with some difficulty at the foot of the stage, tickets to which cost hundreds.

They’re soon looking up at the round smile and rounder spectacles of a little man in a big suit, whose grey ponytail wags behind him like a moomba’s tail.

The man is Japanese video game performer Nobuo Uematsu, and he bows and departs as swiftly and gracefully as he appeared. Most of the music we are to hear tonight is his doing, and the 15 seconds he is on stage is enough to cue raucous applause. Conductor Arnie Roth soon takes his place, dressed identically and with exactly the same must-be-an-orchestra-guy hairdo. Without further ado, Prologue.

This song’s dreamy motifs have traditionally introduced – or at the very least appeared in – every Final Fantasy game ever, but it anti-shadows a slew of compositions that Roth and the Distant Worlds Philharmonic have never performed before, until this Sydney show.

The world premiere of The Oath visibly makes people well up. Final Fantasy VIII’s love story is melancholic throughout, and becomes exceptionally tragic if you adhere to the theory that the main character is mortally wounded at the end of disc one – there are four discs; this was PS1-era stuff – and that the rest of the game is a moribund mosaic of his unfulfilled hopes and dreams as he passes away.

Due to overwhelming online demand, Final Fantasy VI’s Searching For Friends also appears during the live show for the first time, to squeals of delight. Its retro 90s charm plays on screens above the orchestra, remembering a distinctly adult story that did not defy the cutesy 2D sprites of its major and minor players, but seemed to absorb them. It’s a story where the villain wins, at least initially. Searching For Friends is so named because at the end of the world, that’s what you essentially have to do in order to resume saving it. Most Final Fantasy fans experienced this as relative children. We were those 2D sprites.

Facebook Twitter Pinterest ‘What should be a niche interest has become a cult.’ Photograph: SGC Media

At intermission, boys dressed as giant yellow chickens (chocobos) explain the intricacies of why it’s actually “Aerith” and not “Aeris” to girls in plain clothes – and girls dressed as bobble-headed white teddies with red pom-poms on their heads and purple bat wings (moogles) explain to boys in plain clothes why Final Fantasy X-2 was actually not a crime. There is much passion in the voices wailing from the cosplay tributes, and much uncertain nodding from the plain clothes confusion brigade. Final Fantasy is its own nation-state, replete with eccentric customs and impenetrable cultural norms which, as the hubbub suggests, are pleasingly universal.

If The Oath dug the well, then Final Fantasy X’s To Zanarkand causes it to overflow. I once walked by a house where someone was playing this on their piano and hunched into a ball for 20 minutes thinking about all my romantic mistakes. The entirety of row O does more or less the same thing inside of a minute. “Tidus was real to me!” a girl declares, an impassioned ode to said Final Fantasy X’s protagonist who turns out to be both final and fantasy.

2006’s Final Fantasy XII marked the beginning of what would be Final Fantasy XIII’s radical, oft-maligned departure from the series in 2010. It plays different, it feels different, it sounds different – and it’s also being re-released in remastered form this month after 11 years.

There had been much changing of the creative guard by then, and though Nobuo was no longer at Final Fantasy’s compositional helm, Flash of Steel – instantly familiar as largely the work of Hitoshi Sakimoto to anyone who enjoyed Sega’s artful strategy RPG, Valkyria Chronicles – is indisputably rousing. It galvanises the concert hall well for tribal Final Fantasy VII jaunt Cosmo Canyon and, suddenly, the apex of the evening.

“There are over 100 compositions in the Distant Worlds vault,” Roth intones, “but only one that necessitates a pipe organ.”

So saying, a dapper pipe organist appears as if he was always there, and an extended medley of Final Fantasy VI’s dancing mad best ensues (one of which is entitled Dancing Mad). Many are left wondering how any one instrument can perform the extended solo miracles just witnessed, bewildered by the realisation a 16-bit game released in 1994 had music written specifically for pipe organ in it. During the epic and brooding strains of Terra’s Theme, the multi-keyed muse seemingly carries the entire orchestra on its back on the way to Distant World’s ultima weapon.

Nobuo Uematsu appears onstage once again, the composer and pianist shyly suggesting he would like to sing tonight. Not alone, you understand. He shuffles among the choir to bellow One-Winged Angel’s infamous Seph-i-roth! refrain with you, me, that girl, that guy and a dizzy parade of hundreds who will be loudly serenading the city with it on the way home, long after the last dramatic pizzicato.

• The Distant Worlds: Music from Final Fantasy tour continues throughout 2017, with concerts in Singapore, England, France, Canada, Japan and the US.