Ecue, I know that INT and MND are not a stat based on job (i.e. one is a stat for white magic and one does the same for black mage).
Banish is affected by Int. I've tested this personally. It is NOT affected by MND, because it is an *attack* spell. Same goes with Dia, for that matter.
Damage *I* take from spells Directly relates to my MND stat (regardless of whether they are white or black magic), I've tested this personally. It is not affected by INT, because INT is about your attack abilities in magic, not your defense.
These are not seperate entities for white and black, but it may seem so because Most white spells are defensive magic and Most black spells are offensive magic, and there are not a lot of spells that are otherwise.
Your ability to cast Enfeebling, Elemental, Divine, and Dark spells is affected by your Intelligence, regardless of whether they are white magic or black magic. Your ability to resist these kinds of spells, is based on your MND, solely.
Test this sometime if you don't believe me. Go find a carrion worm, and attack him from a distance. He'll cast Stone on you. Check the damage. Get an item that adds +3 INT (but no MND), put it on, he'll do the same damage. Get an item that adds +1 MND, put it on, and it'll cut the damage by a percentage based on your current MND, every time, guaranteed.
Your ability to cast Healing and Enhancing spells is affected by your Mind, regardless of whether they are white magic or black magic. You don't resist this kind of spell. (What are you going to do, say No to a Cure?)
Blaze Spikes is affected by MND, not INT, regardless of the fact that it's a Black Magic spell.
Banish is affected by INT, not MND, regardless of the fact that it's a White magic spell.
There are others, but those two are the most notable (and most seen) by many players.
Some of these I'm not completely familiar with (most notably STR and CHR) as they don't pertain to my character, but INT and MND are my two most important stats, and I've tested how much they affect everything I do. I am a Black Mage / White Mage in game, and spent perhaps two hours a long while back testing these theories; I needed to know how much it was worth spending money on which stat increasing items.
I would like to say, though, that your descriptions of Agility and Dexterity explain a good bit more than mine. =)
Edited, Fri Nov 28 14:06:20 2003 by SilverwolfDarksoul