Part 25: Chronopolis - Chrono Cross Guide - IGN

Once everything is done, go to the Dead Sea Ruins (Home), and interact with one of the three glowing points in the water.

Part 15: Party Recruit - Chrono Cross Guide - IGN

Part 24: Characters & Techs 2 - Chrono Cross Guide - IGN

Part 10: S.S. Invincible - Chrono Cross Guide - IGN

Part 27: Into Terra Tower - Chrono Cross Guide - IGN

Part 26: Lucca's Orphanage - Chrono Cross Guide - IGN

Part 12: Mount Pyre (Another) - Chrono Cross Guide - IGN

Part 25: Chronopolis - Chrono Cross Guide - IGN

Part 15: Party Recruit - Chrono Cross Guide - IGN

Part 04: Termina (Another) - Chrono Cross Guide - IGN