This is everything you need to know about how to recruit Norris in Chrono Cross: The Radical Dreamers Edition.
How to Recruit Norris
Once you have Radius in your party, you’ll have to return to the Viper Manor Ruins (Home World). There, one of the only parts left is the basement, which you can travel down to.
Talk to Norris, who you’ll find down to. When Serge explains the situation, he will offer a boat and ask to join your party.