...did you play the game?
Chrono Cross began 20 years Later, and I meant when Serge came in the other world. Kid's canon age is 16, meaning that Lucca took care of her 4 years after Lavos (or 1004 AC). Then after 1010, Lynx began all the stuff to get back access to the Flame due to the stuff happened for the Prometheus Circuit and Serge, and back then Kid was just a little kid, meaning that Lynx went against Lucca in a period that was around a bit more than 10 years after CT events.
Now, explain to me how Lucca would get so damn weaker in 10 years, because she was a Teen in Trigger.