HAVING A WEAPON DEAL DAMAGE BASED ON SPIRIT STAT?

With my limited scripting knowledge, I've managed to find a way for you. I'm assuming you're still asking about VX.

Open the script editor (F11 or under tools). Then, look for a script named "Game_Battler" and Ctrl+F for "def make_attack" (or look for line 642).

You will then see:

def make_attack_damage_value(attacker)
damage = attacker.atk * 4 - self.def * 2 # base calculation
damage = 0 if damage < 0 # if negative, make 0
damage *= elements_max_rate(attacker.element_set) # elemental adjustment
damage /= 100

Replace it with:

def make_attack_damage_value(attacker)
damage = attacker.atk * 4 - self.def * 2 # base calculation
damage = attacker.spi * 4 - self.def * 2 if attacker.element_set.include?(17)
damage = 0 if damage < 0 # if negative, make 0
damage *= elements_max_rate(attacker.element_set) # elemental adjustment
damage /= 100

That adds one line of code that checks if your attack is using the element with the ID number of 17 and modifies your damage (also making it so that the previous line doesn't matter). You can change the 17 to whatever you want. You can also modify the calculations too.

Then, open the database. Click on the system tab and create an element 17 (or the number you picked, or rename an already existing one). Name it something like "Magic Staff" or something to remind you of what it's for.

After that, create your weapon and under the elements section, check the fire element and the element you just made.

Since by default only the most effective element will be used when calculating damage, to avoid your "Magic Staff" element accidently making your attack stronger than intended, you should probably set every monster's resistance to it to F. This is assuming you'll always be using at least 2 elements on the weapons using this element. If not, don't do this or the monsters will be healed from every hit (F is -100%).

post=92520
With my limited scripting knowledge, I've managed to find a way for you. I'm assuming you're still asking about VX.........

This is exactly the way I would have explained it. I love elements.

To bypass the funky/stupid element system, go get some Mithran scripts on rpgmakervx.net and set up multiplicative damage for element rates. That way, having a 100% damage element (spirit-based damage weapon tag) and 200% damage element (fire) will mean you do (1.0 x 2.0) damage... further meaning that you'll still do 200% damage.