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 25: Chronopolis - Chrono Cross Guide - IGN

Continue Plus - Chrono Cross Guide - IGN

Part 21: Characters & Techs 1 - Chrono Cross Guide - IGN

Part 17: The Einlanzer - Chrono Cross Guide - IGN

Part 16: S.S. Zelbess - Chrono Cross Guide - IGN

Part 01: Arni Village (Home) - Chrono Cross Guide - IGN

Part 25: Chronopolis - Chrono Cross Guide - IGN

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

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

Part 23: The Dragon Tear - Chrono Cross Guide - IGN

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

Part 06: Viper Manor (Another) - Chrono Cross Guide - IGN

Part 05: Nikki's Path - Chrono Cross Guide - IGN

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

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