With Chrono Cross's Japanese release imminent, more information on the world and characters has become available. There will be two parallel worlds in Chrono Cross, the positive and negative worlds. Somehow the storyline will intertwine between the two worlds, and many of the characters will have different or opposite personalities in the opposite worlds. Lucca of course is scheduled to appear in the game, and supposedly the other characters of Chrono Trigger have a high chance of returning as well.
The focus of the storyline will probably be around the legendary Frozen Flame, a treasure said to be able to alter history and dominate the world. More characters in the world have also been revealed, you can click here to see the new character designs.