You could edit your charecters into being gods and save them under a different name, beat the demons, ogres, and giants, then just place all of the stats of the God-ish party back to what the orignal parties stats are... I've only done it a couple of times, but it works.
I had killed him a long time ago, I just didnt have farsight back then, by the way... do you know whats up the the two dead guys in Corta? I can't figure out who did it...
In A3 I was trying to beat the 4 crystal souls over and over again, but i couldnt, so I used the charecter editor to take me out of town, now i cant get to them....