Los Angeles-based company Hydra Entertainment assisted with creating the script alongside Hasegawa, in addition to writing assistance from Hollywood staff. The storyline was designed to complement and set the stage for the events of Final Fantasy XV without revealing major plot elements from the game. The film was created for a primarily English audience, with the script translation handled by Square Enix's in-house localization team. The narrative was split into three acts, with production on the CGI element of each act finishing before beginning work on the next. This meant that last-minute adjustments were taking place until the end of production. As many team members were Final Fantasy fans, frequent nostalgic references to earlier entries in the series were included. The central theme for the overall story of Final Fantasy XV was the bond between father and son: Kingsglaive represented the theme from the father Regis' point of view. According to Nozue, another key element during the early segment of the film was displaying how the world's society sees Regis's responsibilities, along with the emotions involved in such a role. The main goal for the film's characters was to portray them as normal people with character flaws, rather than magical superheroes. Nyx was an original character created for the film with no connection to the events of the game, intended to act as a medium for the wider audience Kingsglaive was aimed at. Nyx also provided a medium for the story themes surrounding immigration issues, which in turn brought the audience closer to the main cast. While Nyx was original, multiple key characters from the game played prominent roles, particularly Regis, Lunafreya, and Ardyn. Lunafreya was highlighted as the "keystone" connecting the game, the film, and the anime series Brotherhood. While her role in the film was not an active one, her strength was conveyed through her single-minded devotion to her goals. Design Prior to full production, the team created a tech demo in 2012 to test the creation and movement of highly detailed models and environments. This tech demo was titled Agni's Philosophy, which also acted as a test demo for the Luminous Studio engine which would be used for Final Fantasy XV. Character designs and modelling was overseen by Business Division 2; the team was led by Kazuaki Iwasawa, the character model supervisor. The character Crowe's hair was based on the hairstyle for the main female protagonist of