Ah, got it: If you choose not to fight him, he just turns around, says "...", and doesn't do anything. If you leave, then come back, he's no longer there. If you try to talk to him, nothing happens.
If you do fight him, though, instead of blabbing about Gasapr and stuff, he says: (after the "Glenn's curse will be undone" thing")
Magus: Ha...whoever would have thought...that you fools could defeat me... {line break}
It looks like...this will be...my last...farewell... {line break}
Schala...
*He turns around and dies*
That would make the characters' interaction with Schala make more sense.
(Also, I'm kind of new to writing script... is {full break} when the text box clears and a new set of text appears? And is a {null break} the end of a dialog? If so, I'll have to comb through my script and redo that... -_-)