Characters

Playable characters are distinct player-controlled characters in Star Ocean 2. There are 12 possible characters to include in a party. Apart from brief periods in the story where the player has only one character in their party (always the originally-chosen protagonist), the number of characters in a single party ranges from two to a maximum of eight. Only Claude C. Kenni and Rena Lanford are mandatory.

Celine Jules
Jules briefly joins the party regardless of whether the player declines her solicitation to venture into Cross Cave. After completing the mission in Cross Cave, the player may then decide whether to add her as a permanent member of the group. Because of the importance of spellcasting early in the game, it is highly recommended that first-time players admit Celine Jules into their party.

Protagonist-dependent Characters
Two of the characters can only be acquired if the player chose Claude or Rena at the start of the game. Dias Flac will only join in a Rena-driven story; Leon D. S. Geeste will only join a Claude-driven story. Because both Dias and Leon require specific plotline choices by the player, and so it is entirely possible to unintentionally miss the opportunity to add one.

Secret Characters
Several characters are considered "secret" characters, and admitting one character may permanently exclude the player from acquiring another. The player may locate and admit Opera Vectra and Ernest Raviede, or the player may find and admit Ashton Anchors. The player cannot admit Opera and Ashton, and one cannot find Ernest without Opera. Because finding and admitting Opera requires more precisely timed Private Actions, players more frequently acquire Ashton in their play-through or acquire no secret character at all. While many experienced players tend to prefer Opera over Ashton for combat, given her healing-abilities late in the game, there is no objectively-better selection, and a full experience of the game is impossible without playthroughs with each character.

Preclusive Characters
Two other characters mutually exclude each other. One may admit either Precis Neumann or Bowman Jean, neither, but not both.

Chisato Madison and Noel Chandler
Two characters are acquired only in the second disc of the game. Chisato Madison, who, like other secret characters, must be acquired through a technical use of Private Actions, and Noel Chandler, who may be acquired by the payer through the normal story progression.