The term, -straight- from the PHB, is 'weapon damage dice.'
Not damage die. Damage dice.
p276.
'Weapon Damage Dice: A [W] in a damage expression stands for your weapon's damage dice.'
The term, as used in the books, refers to [W] using the plural. The term in the weapon chart uses the term 'weapon damage.'
Nowhere in there does it say 'damage die' to describe a specific weapon characteristic.
So yes, misinformation.
Vorpal does not even refer to 'weapon damage'. It refers to damage, period. That means it includes sneak attack, hunter's quarry, it's own daily power, and it's own critical damage dice. So even an argument about weapon die vs. dice is irrelevant to this discussion.
As for my algebra:
Let the average die roll for an exploding die be
A, and the number of sides of the die be
d.
1/
d of the time, the die will come up with a roll of
d and you re-roll and add more damage, using the same exploding rule. This extra roll is a distinct event, and itself has an average roll of
A. As an example with a d4, 1/4th of the time you're going to roll another d4, and that d4 has the same average die roll as the original, because it works -exactly the same-. The total when this event happens is equal to the original die roll (you still get the 4 you rolled on a d4) plus any additional dice.
d-1/d of the time, dice work just as they normally do. The average damage for this is simple to calculate. You take the minimum damage, plus the maximum damage, and divide that by 2. It's pretty much the same as if you rolled a (
d-1) sided die.
Converting this to an equation you get:
Code:
A = (average damage of dice when not exploding X probability of not exploding) + (average damage of dice when exploding X probability of exploding)
A = [(1+d-1)/2 X (d-1)/d] + (d + A)/d
A = [d/2 X (d-1)/d] + [1 X (d + A)/d]
A = [d(d-1)/2d] + [2/2 X (d + A)/d]
A = [d(d-1)/2d] + [2(d+A)/2d]
A = [(d^2 - d)/ 2d] + [(2d + 2A)/ 2d]
A = (d^2 - d + 2d + 2A) / 2d
2dA = d^2 + d + 2A
2dA - 2A = d^2 + d
A = [d^2 + d]/[2d-2]
My initial calculations were wrong, sadly. Flipped a negative sign.
And I admit my mistake there.
This is how the average damage of an exploding weapon turns out:
1d4 = 10 damage
1d6 = 10.5
1d8 = 12
1d10 = 13.75
1d12 = 15.6
I'm willing to say then that the average damage for a vorpal 2d4 weapon is more than the average damage for a vorpal 1d12 damage weapon by 4.4 damage per [W].
However... is this intentional that a high crit weapon will do more damage vorpally than a non-high crit weapon, not taking crit effects into consideration? It just might be.
Regardless, the vorpal property does not refer to weapon damage dice, or weapon damage die, but 'any damage die'.
That's the operative word. -ANY- damage die.
Bonus dice from Sneak attack? That's damage dice.
Bonus dice from Vorpal's power? Damage dice.
Bonus dice from critting with it? Damage dice.
Bonus dice from critting with it if it were a high crit weapon? Damage dice.
Bonus dice from -any- source? Damage dice.
The [W] portion of the weapon's damage is therefore irrelevant to this discussion entirely.
Another use of damage dice in a power:
Staff of Fiery Might.
Are you saying that if a minotaur uses a clerical power with it that has the Fire Keyword and the Weapon keyword, say Avenging Flame (does 2[W] fire damage)... that with a +1 Staff of Fiery Might, he'd get to reroll whichever 2 dice displeased him? Or that he has to roll his dice in bursts, each individually?
In order for Vorpal to work the way you claim it does, you'd have to roll each 2d4 for the falchion seperately, otherwise the player'd just mix and match dice willy nilly to get the same benefit as if you didn't allow each die to explode.
In other words... the power cannot feasibly work in execution the way you want it to. Therefore it -must- work in the way it is worded.
