It may seem like a long time ago, but it was only in 2010 when Final Fantasy XIII was first released for the Xbox 360 and PlayStation 3. Later in 2014, it made its way to PC and finally to mobile devices in 2015 but only for Japanese gamers. The game is set on the world of Gran Pulse and the spherical man-made world, Cocoon, that floats above it. Both of these worlds are influenced by the fal'Cie, which are god-like beings who can impose their will onto humans by branding them as "l'Cie" and sending them visions of their "Focus", the task they must complete. If the task is completed, the person gets to "live forever" in crystal form, if they fail to achieve their task, they become mindless monsters known as Cie'th.

Though the game received mixed reviews with many critics disliking its more linear gameplay, Final Fantasy XIII was still considered a success and went on to have two sequels. But even for the most dedicated fans who have by now memorized the lore of the game, there's a lot about this popular Final Fantasy sequel that they don't know. Here are ten things about Final Fantasy XIII you need to know.

10 It Was Originally Destined For The PlayStation 2

Final Fantasy XIII was originally intended to release for PlayStation 2 however, after the positive reaction that Square Enix received over its tech demo, it decided to move development over to the next generation of consoles.

It was the first game to be developed using the new Crystal Tools engine, with the team initially thinking that a new engine would expedite the development process. However, using the Crystal Tools engine actually ended up causing a delay because the new engine had to also accommodate the other titles that were being developed at the time.

9 It's Part Of The Fabula Nova Crystallis

Though everyone is aware of the link between Final Fantasy XIII and its two sequels, many players don't realize that it is part of a bigger collection of games called Fabula Nova Crystallis: Final Fantasy, with its name meaning "new tale of the crystal" in Latin.

The idea is that the games have different characters and different worlds, but share the same crystal mythos at their core. The series includes Final Fantasy XIII, Final Fantasy Type-0 (Originally titled Final Fantasy Agito XIII), Final Fantasy XIII-2, Lightning Returns: Final Fantasy XIII, Final Fantasy Agito (a companion to Type-0 for mobile devices), and Final Fantasy Awakening (a follow-up to Agito, also for mobile). Originally, Final Fantasy XIV was going to fall under the Fabula Nova Crystallis umbrella with its original title being Final Fantasy Versus XIII, but this was later changed.

8 It's The First Multi-Platform Franchise Title

Final Fantasy XIII was the first multi-platform title in the franchise, breaking a long-running tradition of the recent predecessor titles being Sony console exclusives. The game had initially been confirmed as a PlayStation 3 exclusive, so when it was announced that it would also be released on Xbox 360, fans in Japan branded Square Enix's CEO Yoichi Wada a liar and even sent him death threats.

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It was also the first Final Fantasy title to receive an official release for China and Korea, and additionally was also the first Final Fantasy title where Japanese voice-overs could be enabled by the player.

7 Previous Characters Were Used As Stand-Ins During Development

Here's a little bit of interesting trivia for Final Fantasy fans out there: while Final Fantasy XIII was still in early development stages, the team used character models of previous Final Fantasy characters as stand-ins for the characters that had not been finished for XIII yet.

The character models used were Yuna and Rikku from Final Fantasy X, and Vaan and Ashe from Final Fantasy XII. Interestingly, the development team for XIII was led by Yoshinori Kitase, and as such the team was largely the same as the one that worked on Final Fantasy X and Final Fantasy X-2.

6 It's The Fastest-Selling Final Fantasy Title

Final Fantasy XIII became the fastest-selling title in the franchise's history, selling more than one million units on its first day of release in Japan and over one million copies in North America during the first month of its release.

Square Enix announced in 2014 that the Final Fantasy XIII series, encompassing both of the sequels, had shipped over 11 million copies worldwide in total, and by 2017 it was announced that Final Fantasy XIII alone had sold more than 11 million copies worldwide.

5 The Characters Crossed Over Into Other Media

Final Fantasy XIII proved so popular that the characters appeared in other media. For example, both Lightning and Snow featured in an advert for the SUV Nissan Kicks car in China. Lightning also appeared in a Sony PlayStation advert that featured many protagonists from multiple different titles, where she is seen talking to Uncharted's Nathan Drake.

One of the strangest collaborations has to be between Square Enix and Louis Vuitton, where Lightning modeled for the Season 4 spring/summer collection of clothes and handbags.

4 There Is Some Missing Music

Final Fantasy XIII was the first main title in the franchise to not include either original "Prelude" or the "Victory Fanfare" music, despite both being two of the most recognizable musical pieces in the series.

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Instead, the new "Glory's Fanfare" music played when players were successful in battle. Additionally, while "Prelude" doesn't feature properly, there is a piece of music called "The Sunleth Waterscape" that features a short and fast piano mix that sounds similar, though it is not played as the prelude music, which is instead a new track called "Prelude to Final Fantasy XIII".

3 There Were Plans For DLC

There were originally plans for Final Fantasy XIII to receive downloadable content; there is even information found in the game data that indicated a new area called The Seventh Ark. This unused area was an Ark from Gran Pulse that featured the fal'Cie Nemesis.

Hacking into the area allows the player to see a cutscene where the heroes speculate that Barthandelus plans to use the Arks to unleash Pulse weapons on Cocoon and destroy it from inside. Given how successful the game was, it's likely that the DLC was scrapped in favor of starting work on the sequel, Final Fantasy XIII-2.

2 The Number 13 Is All Over The Game

Final Fantasy XIII alludes to the number 13 many, many times throughout its gameplay. Just a few examples of this are: the game has 13 chapters, the flashbacks cover 13 days, and there are 13 party members in total when you include all the Eidolons, counting the Shiva Sisters as two people.

Additionally, the number 13 appears often, such as in Leviathan Plaza when looking at the Edenhall, players can see the number 13 on the left wall of the entrance, and also the Cocoon scrip on the arm of the Manasvin Warmech reads "CA13."

1 There Are References to Other Final Fantasy Titles

Final Fantasy XIII is rife with references to past Final Fantasy titles, such as the fal'cie sharing names of past summons, an NPC child quoting Kefa's line of "Run, run, or you will be well done!", and some of the weapons alluding to other characters, such as Lightning's Lionheart Gunblade referencing Squall from Final Fantasy VIIIto name just a few.

Additionally, many fans believe that the opening to Final Fantasy XIII pays tribute to Final Fantasy VII, as there are parallels between Cloud and Lightning, with Final Fantasy XIII starting aboard a train and Lighting telling Sazh that she is no longer a soldier. Furthermore, the Manasvin Warmech, the first boss, pays homage to the first boss of Final Fantasy VII, the Guard Scorpion.

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