Tales of Xillia‘s Gaius and Muse are playable party characters in Tales of Xillia 2, the latest issue of Jump confirms.
(Warning: the following descriptions are spoilers for the first Tales of Xillia .)
Muse: (CV: Asami Sanada)
Milla’s sister, she is a great spirit with the power to rip through dimensions. For some reason, she has again showed up in the human world.
Gaius (CV: Ryutaro Okiayu)
King of Liese Maxia, he holds a desire to protect the weak, keeping his social status hidden when in action.
Additionally, the magazine reveals two new, non-party characters:
Ridou (CV: Koji Yusa)
A Doctor Agent at Clanspia Company. He was seen in the fourth trailer, released at the Tokyo Game Show.
Chronos (CV: Junichi Suwabe)
One of the three original spirits alongside Maxwell and Origin, and guardian of the land of Canaan. (I think.)