Tales of the Abyss Nebilim Catalyst Weapons?

I've read plenty of times that the catalyst weapons increase in power for every enemy you defeat....Does this happen before or after the Nebilim fight? After would render utter uselessness to me. I could really use some help before the Nebilim fight and power them up off weak enemies in order to assist fighting Nebilim later on. I'm at Yulia city for the third time and currently on the second playthrough.



EDIT: Forgot to mention, Do all of the Catalyst weapons have this Power Rising Effect?

The power raise only effects the weapons after you beat neblim on your current play through personally seem pointless as neblim is the hardest boss in the game(imo) And yes all catalyst weapons work there are 6 of them one for each playable character.

And i should also mention something i found out the hard way [spoiler] the sword of loreli [/spoiler] is not a catalyst weapon even though it uses the same star on a sword symbol as they do.