The game is a prequel to the original Baten Kaitos game, taking place in the same fictional world twenty years prior to the events of the first game.[8] While many of the locales are present in an altered form, the game also features several new locales, such as the continent of Hassaleh, and Sedna, a fantastical town made entirely out of clay sculptures.[3] While featuring a new cast of playable characters, younger versions of characters from the original game can be found scattered across the game's world, albeit twenty years younger.[8][3] The overall theme of the game's world is that of a struggle between "pro-magnation" (the power of hearts, wings of the heart, and magic) and "pro-machination" (mechanical) forces; having many parallels to the modern concept of industrialization.[3] The main race of characters are human-like in nature, but possess bird-like wings on their back that assists in flying in small short bursts.[5] The player plays the role of an unseen guardian spirit who can communicate to Sagi, the main character, who is a "spiriter" - a rare type of person who can communicate with said spirits.[5] Communication is limited to pre-set dialogue tree option selections.[5] Other playable characters include Guillo, a mechanized synthetic, genderless life form of which Sagi knows through working through the "Dark Service" force Sagi does for a living, and Milly, a sheltered, runaway young woman who decides to travel with the two.[5]