Each new Final Fantasy is a big deal, but after a long and troubled 10-year development, Final Fantasy 15 may be the biggest of them all. First announced as a spin-off of the long-running RPG series' 13th entry, it has endured changes in personnel, changes in management, a switch in platforms, a change of name and increasingly bitter fan impatience to become one of Square Enix's most important ever releases.

It was originally announced as Final Fantasy Versus 13 at E3 2006, and was planned to form part of a multi-game project centred around Final Fantasy 13 – which included Versus 13 and Agito 13. It was never made clear why Versus 13 and Agito were eventually rebranded, but it's reasonable to assume the reception 13 received upon release had something to do with it.

With its dazzling announcement trailer and the creator of the Kingdom Hearts series, Tetsuya Nomura, in place as director, fans eagerly awaited more details on a game that was to focus on the darker side of Final Fantasy 13. After its initial announcement and glimpses of its Noir-ish, futuristic world in trailers released from 2007 to 2009, things went silent until a substantial new trailer in 2011.

It was in this new footage that fans first saw its stylish, action-oriented gameplay and an open world that looked much grander than what had been seen in Final Fantasy 13. This impressive look at the game showed fans that Versus 13 still had a beating heart, and that it hadn't – as many fans had assumed – become vapourware.

The question remained however: what was the cause for this delay in showing Versus 13? With the release of 13, and Agito 13 renamed Type-0, Versus 13 was being left in the dust. This was partially due to engine changes, causing the game to be delayed even further. After the announcement of Final Fantasy 13-2, Versus 13's future looked rockier than ever, and Square Enix's repeated attempts to dispel rumours of its cancellation didn't ease fan concerns.

The pressure was beginning to mount.

After it's 2011 trailer, the game went silent again due to radical changes that were happening behind the scenes at Square. The game made another significant shift – this time to current generation consoles – and to bear the brunt of the additional development required, the team from Type-0 came over to assist. With them came director Hajime Tabata, who was to co-direct Versus 13 alongside Nomura.

Discussing this shuffle in 2015, Tabata told IGN (via a translator): "In terms of how much it had progressed in terms of development, Versus 13 was around 20-25%. In terms of character designs or visuals, nothing really had been fixed at that point. We were still working on updating it and revising those designs."

It was around the time of this power shift that the game was rebranded internally as Final Fantasy 15.

Final Fantasy 15
Some of Final Fantasy 15's boss encounters are enormous in their scale Square Enix

Tabata was eager that a massive restructuring of the game take place, with huge concepts, characters and features scrapped entirely. Versus 13 as the game it once was, was no more, but looking at the setting and ideas seen in some footage, it seems a lot of scrapped concepts went on to inform Kingsglaive: the CG movie that takes place during the opening chapter of Final Fantasy 15.

At E3 2013 the game was reintroduced as Final Fantasy 15. However, after this shock announcement, the game disappeared once more, and just over a year later Nomura was taken off the project, leaving Tabata to at the helm.

Tabata was eager to ensure that fans were no longer left in the dark, as they had been under Nomura's leadership. So it was from this point that the development team took a much more transparent approach and updated fans regularly. This was achieved through the "Active Time Report" YouTube series, in which Tabata and his team would stream updates on the game's development.

Suddenly Final Fantasy 15 was enjoying a more traditional development cycle, which also adopted a more open mentality more commonly seen in the development of Western games than those of historically secretive Japanese studios.

It was during the first Active Time Report that fans got a glimpse at Final Fantasy 15 in action, and it was becoming clear that the series rule book was being torn apart.

Final Fantasy 15 pushing car
Lead character Noctis and his pals pushing their broken-down car along the road. A metaphor? Square Enix

"The fight is with nostalgia as much as anything else," Tabata told Eurogamer. "Every player has their own memories and feelings toward different titles in the Final Fantasy series. At bare minimum, people have a graphical style they particularly like, or particular characters and universes. But deeper than that they want to feel the same feelings they had when they were kids, playing these games for the first time. They want to play a game that allows them to relive the excitement of the past, while also exceeding it in some way. But we decided early on that this game has to stand alone from all of the others; it can't just be a conglomerate of all the past titles."

Final Fantasy 15 was to be a game that dared to take the series into a new direction, compounding its need to be successful. Initially however, players didn't react well.

A demo for the game, called Final Fantasy 15: Episode Duscae, was bundled with an an HD rerelease of Final Fantasy Type-0 for Xbox One and PS4. It offered players their first taste of Final Fantasy 15's new gameplay. For those following the game's development the action-oriented gameplay came as no surprise, but the demo's lock-on system and frame rate were heavily criticised. Following fan feedback, changes were made, and Final Fantasy 15 slowly took its final form, with a further demo released earlier this year.

Final Fantasy 15 has existed for more than a decade, and whether it fails or succeeds, its story is one that will be pored over for many years to come. With the immense amount of money that has been poured into its development, for Square Enix it needs to be nothing short of an astounding success.

We don't know yet if the tumultuous journey will be worthwhile for players old and new, but ten long years after its initial announcement, we'll very shortly get to find out.

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