I know of no FAQ, and the spell text is not specific, so this could be argued either way and it's really up to the GM to decide.
Consider this:
An 18th level cleric or an 18th level sorcerer could animate 72 HD worth of undead by casting the spell twice to get 36 HD each time. It would not be unfair for a party of adventurers attacking the lair of such an 18th level necromancer to have to face 72 HD of undead. In fact, it would be expected.
But a 9/9 sorcerer/cleric who is also 18th level would present a much weaker challenge if he could only animate 36 HD of undead. There would be no benefit in limiting him to a "common pool" of undead HD. Applying such limits would just make him weak.
That dual-class character is already limited enough by being stuck with 4th level sorcerer spells and 5th level cleric spells (instead of casting 9th level spells like other level 18 spellcasters could). Furthermore, if he's animating them during a battle, he can only animate 18 HD at a time because his caster level is only 9, not 18. So he's significantly weak as it is.
Therefore, in my opinion, letting him have 36 HD from his sorcerer animations and another 36 HD from his cleric animations is not game-breaking and should be allowed.
Magic section same spell same effect rule.
I should have been more clear in my first response.
The text of the spell says "Caster Level", not "Character Level" and certainly not "Sum of all Caster levels". It doesn't matter that the character has multiple classes or not. Based on that, I am about 99% sure that you should do it as follows:
If he is casting Animate Dead from his sorcerer list, determine the maximum number he can control and the maximum number he can animate per casting based on his sorcerer level, and when he is casting Animate Dead from his Cleric list, determine those maximums based on his cleric level.
At the time of casting, those are his limits based on the class level of the class from which he is casting. He cannot exceed them.
In the example of the mystic theurge, his caster level in both classes is 13, so he can animate 26 HD per casting to a maximum of 52 HD. If he had Magical Knack with sorcerer, then when he casts Animate Dead as a sorcerer, his caster level is 15 (limit 60 HD of undead) but his caster level as a cleric is still 13 (limit 52 HD).
That's the way it should be done. Class of spell being cast sets the caster level FOR THAT CASTING and he cannot exceed the limits AT THE TIME HE CASTS IT.
My previous post presupposed this (I should have been more clear) and I was just answering more of a "Why not let him combine the pools" question. As for combining the pools, which I'm sure is not the right way to do it, I think it would not be overpowered, but I would never let the combined pools exceed his character level or else it would get overpowered, as in the case of the mystic theurge combining for 26 levels when his character level is only 16.
Magic section same spell same effect rule.I get that if you cast a spell say a divine fireball and arcane that they would be the same assuming same level of caster. The question is about the stacking or the hd of undead one can have....
same effect from same source means it does not stack
These seems like a decent FAQ topic given that Mystic Theurges are now much more accessible with the SLA FAQ.
same effect from same source means it does not stackMagic section same spell same effect rule.I get that if you cast a spell say a divine fireball and arcane that they would be the same assuming same level of caster. The question is about the stacking or the hd of undead one can have....
And I don't see how that rule really applies. The section for stacking indicate it is referring to bonuses (or penalties) to some attribute.
http://www.d20pfsrd.com/magic#TOC-Combining-Magic-Effects
This is not case in this situation. There is not bonus to any attribute granted by the spell.
I would go with the track separately for each class.
The rules for stacking goes for all effects. This effect gives you the ability to control undead up until a certain amount of HD, you can't increase that amount by using the same ability again.
It's almost a text book case.
I have an ability -- I want to increase the limit of that ability can I use the same source to increase that limit? No -- same source doesn't stack unless it specifies it does.
Consider protection from energy -- same source doesn't stack but it's not a "bonus" -- same with stoneskin, and other such things -- same source doesn't stack unless it specifies it does.
The HD pools for undead ties to the caster level of the class used to cast animate dead, so two(or more) seperate pools. Handled seperately.
And it isn't specified, but most play with the pool being a seperate attribute, and not locked to the casting of animate dead. So the spell is not setting the HD limit, it's just reminding you of the limit. And in that situation, the stacking rules don't apply.
This makes mystic theurge sort of good for necromancers. The reason I say "sort of" is you have two smaller pools allowing you more HD in total, but a single class(caster level) necromancer can have a single tougher undead, which can be an advantage.
I'm not sure what RAW thinks about animate dead cast from items. My interpretation is:
They have their own caster level, which determines how many HD you animate(along with it's material component setting)
And if you don't have a caster level, then they are not under your control - as in they overflow your undead pool immediately.
And I don't think caster level from a spell-like ability gives you an undead pool. Because that would be over the top, IMO.
(maybe not even classes that don't have animate dead on their spell list - like Paladin or Ranger, although I think all casters have a pool.)
I know a lot of people don't like references to 3.5 but there is an NPC in the DMG 2 (Wiz/Cleric/Mystic Theurge) that specifically states casting the spell in each class allows her to control more undead.
The stacking rules and Animate Dead spell aren't changed from 3.5 so I definitely see it as evidence of separate pools per class.
Well I guess it makes about as much sense as allowing everything from two different classes to stack when the come from the same source.
Well I guess it makes about as much sense as allowing everything from two different classes to stack when the come from the same source.
Every similiar feature coming from two classes stacks, for what i can see: BAB, saving throws, number of spells, HP. The only thing i can find doesn't stack are bonuses (with limited stated exception). An undead pool is not a bonus, so it should stack.