Square's role-playing video game Final Fantasy VI, which was released as Final Fantasy III in North America, features fourteen permanent player characters, the largest number of any game in the main Final Fantasy series, as well as several characters who are briefly controlled by the player.

Pixel artist and graphic designer Kazuko Shibuya conceived the initial designs of some of the cast, including protagonist Terra Branford. Monster designer and graphic director Tetsuya Nomura created the original designs and many story episodes for Shadow and Setzer Gabbiani, he also did the illustrations of the cast based on the characters sprites as well as the chibi artworks in the manual. Field graphic designer Kaori Tanaka created the original designs of Edgar Roni Figaro and Sabin Rene Figaro. Yoshitaka Amano once again returned for the promotional artwork, he also conceived the final designs of Shadow and Setzer. A character named Angela was developed, but was ultimately cut from the game. She was to be like a "big sister" to Cyan and wield a whip, allowing the story to explore Cyan's vulnerability and private side.

Co-director Kitase wanted to create many characters that could stand up to be main characters and ensure the story did not revolve around one character, so each character could have something to bring to the table. According to Yoshinori Kitase, one of the game's two directors, one of the themes of production was "everyone is the main character". Kitase also believes that this approach with the game's characters is one of its lasting appeals. Despite having a large cast of playable characters, the game is well known for its subtle revealing of character relationships and backstories over the course of the story. Cut scenes of character interaction also feature simulated "camera movement", with a similar emotional effect found in movies. During the game's development, the whole team contributed to the stories of the game's characters, which were then adjusted for consistency with the story by Kitase. Instead of just being "ciphers for fighting, players would have more choice in what the characters would do, and how that would alter the narrative and invest the player more deeply in the story". To make the characters more distinct, their fighting styles and abilities were made different. Balancing so many characters was a challenge, and as a result Celes and Kefka became bigger characters than initially planned.

Terra Branford, known as Tina Branford (ティナ・ブランフォード, Tina Buranfōdo) in Japanese media, is the first introduced character, a mentally-enslaved Imperial super-soldier gifted with devastating magic. Hironobu Sakaguchi, the creator of the Final Fantasy series, greatly influenced the character's creation. Originally, Terra was to disappear along with the other Espers at the end of the game, but the developers decided it would be a "waste" to have her discover her humanity only to be erased, so she instead lost her powers.

Locke Cole (ロック・コール, Rokku Kōru; also romanized as Lock Cole) is a thief who prefers to identify as a "treasure hunter". Like Terra, Hironobu Sakaguchi was also a major contributor to the character's creation.

He bears a personal vendetta against the Empire for assaulting his hometown, which killed his amnesiac love interest Rachel. Her last word is Locke's name. Driven by the conviction that failing Rachel led to her death, Locke seeks to protect Terra and Celes as he fights with the Returners against the Empire; Locke seeks a means of resurrecting Rachel as a way to right his greatest wrong. This takes him to the depths of the Phoenix Cave to acquire the "rebirth" power of the esper Phoenix. In the end, Rachel urges him to move on to find someone new to protect, giving Celes her blessing to watch over him before departing for the afterlife. He is also featured in the rhythm game Theatrhythm Final Fantasy as a subcharacter representing Final Fantasy VI. Locke also appears in Dissidia Final Fantasy NT, where he is voiced by Yūki Ono in Japanese and Jonathan von Mering in English.

IGN praised Locke as being the connection between Terra and Celes, helping tie the plot together, and having a unique ability to steal from his enemies.

Celes Chere (セリス・シェール, Serisu Shēru) is a former general of the Empire, who was genetically and artificially enhanced into a Magitek Knight following a magic infusion. Co-director Yoshinori Kitase revealed that he put much effort into creating Celes, and that she is his favorite character in the game.