Dodo can join the party at Garam Masala 31 on Flavorful or Spicy difficulty, and if there is at least one open spot in the party, starting at level 130 and sound magic level 65. They use the sound spirit, which is strong against stone, but weak to blade and dark. Their magic has a chance to put enemies to sleep, and can increase allies' spirit (magic defense) with spirit's march. Dodo has exceptional HP, power, and agility, but very weak MP, defense, and spirit.
Over 900 years ago, Sir Vespucci the Sea King (うみのおうじゃ べすぷっちさま) and his band of pirates landed on Valencia Beach, burying their treasure in a cave by the shore. To keep the treasure's location a secret, Vespucci killed his underlings and left the beach. He also wrote a letter to his trusted friend Gomez (ゴメス) about the secrets of not catching gummy frogs, but accidentally dropped the letter before sailing off. Some time later, he came into contact with an enigma and was transformed into a dodo.
During their trip to Valencia Beach, the students of Will-o'-Wisp Academy were abducted by enigmas and taken to the Light Plane. The protagonist, alone on the beach, discovered Vespucci's letter to Gomez in the seaside cave. Much later on, while the party explored the corridors of Garam Masala, they found the dodo and let it join the team.
Trivia
In Japanese, Vespucci's letter is written in Café au Lait Font and uses lots of slang vocabulary. He also exclusively writes in the Hiragana and Katakana scripts, never employing Kanji.
He is likely based off Amerigo Vespucci, a 15th century Italian merchant. He was known for participating in two Spanish voyages of the Age of Discovery, and publishing books that recounted these expeditions.