Might be considerate to tell him what the requirements are.
To get the good ending in Chrono Cross, you have to defeat the Time Devourer by using the Chrono Cross (makes sense no?). Using the CC will free Schala from her bond to Lavos and destroy him. If you simply beat him to a pulp, Schala goes down with him and you get the crappy ending.
~MJE~
