Knight of Ratatosk/Dawn of the New World takes places two years after the events of Tales of Symphonia. The protagonist is named Emil, and characters from the original Symphonia will return. The newest trailer has shown that all party members will return. However, this same trailer depicts Lloyd in an antagonistic light: he fights the protagonists from Ratatosk. Whether this means Lloyd is an antagonist, or a temporary enemy, is uncertain. In addition, screenshots depicting Zelos have been released, implying that the canonical ending of Tales of Symphonia had Zelos live, rather than die.

The player will be able to capture, breed, and level up monsters to fight alongside Emil in battle. The Field Map won't be returning in this game. Instead, a point and clisk system using the Wii-mote will be used to navigate the world. The map that displays the world itself will be the same as the Field Map in Tales of Phantasia, except that the towns will still use their Tales of Symphonia names.