The game will unite both protagonists and antagonists from installments of the main Final Fantasy series. Chaos will also make an appearance as the god of darkness, while a new character, Cosmos, will appear as the goddess of light. It is unknown, however, if these two will be playable or not. Recent articles released in Japanese magazines have stated that the game will have a storyline that requires playing through all of the characters to complete. There will be a minimum of ten main characters (not including their villain counterparts), and hidden characters are a possibility. Characters can gain customizable equipment, and will also be able to earn experience, levels and gil.

Some of the characters are confirmed to have different forms in their EX modes, as well. Ultimecia from Final Fantasy VIII can fuse together with her Guardian Force Griever, like she did in the final battle of the game she originates from. Kuja from Final Fantasy IX is shown in his trance form. Onion Knight from Final Fantasy III can change into a ninja or a sage, the most powerful job classes from the original game, while his adversary, Cloud of Darkness, also appears in her original green form with her two serpent minions.

List of Playable Characters:
Title Hero Villain
Final Fantasy Warrior of Light Garland
Final Fantasy II Frioniel Emperor
Final Fantasy III Onion Knight Cloud of Darkness
Final Fantasy IV Golbez
Final Fantasy V Exdeath
Final Fantasy VI Kefka Palazzo
Final Fantasy VII Sephiroth
Final Fantasy VIII Squall Leonhart Ultimecia
Final Fantasy IX Zidane Tribal Kuja
Final Fantasy X Tidus Jecht