Spellcasting: Stacking monster levels with class levels

[StealthyMark]

There are a few examples of adding spellcasting classes to spellcasting monsters.
Wyrms of the North: Arauthator, Old White Death, old white Dragon Sor5
Zharunkumar, Rakshasa Sor7

In both cases, their spellcasting abilities stack. Arauthator casts spells as a 10th-level Sorcerer, Zharunkumar casts spells as a 14th-level Sorcerer. That's quite easy.

Let's assume for a moment this would be correct (in fact, I think so).

Now, lets have a look at Shamira, female Ghaele. Shamira casts spells as a 14th-level cleric with access to the Air, Animal, Chaos, Good and Plant domains (MM, pg 32).
Does she has domain spell slots?
Does she has the domain powers? All, two or none?

Now, Shamira gains three levels of cleric. She casts now spells as a 17th-level cleric.
Can she cast Shapechange (Animal 9, Drd 9, Sor/Wiz 9)?
Does she gain domain spell slots for Level 1 through 9 or for Level 1 and 2 only?
Does she choose two additional Domains?
Do her level dependant domain powers work at caster level 3 or 17?

 

[DM_Matt]

Just to support your initial assumptions, I started a thread on this a while ago and some WOTC type said that such a fact was an assumption that designers go by internally.

Its said explicitly for one of the monsters in OA that has inherant sorc levels and advances by class level that they do indeed stack.

 

[Henrix]

All your examples (dragons, rakshasas and ghaele*) are quite clear in their descriptions that they have some sort of virtual spell caster levels. Akin to "virtual feats" I suppose!

Now, lets have a look at Shamira, female Ghaele. Shamira casts spells as a 14th-level cleric with access to the Air, Animal, Chaos, Good and Plant domains (MM, pg 32).
Does she has domain spell slots?
Does she has the domain powers? All, two or none?

Now, Shamira gains three levels of cleric. She casts now spells as a 17th-level cleric.
Can she cast Shapechange (Animal 9, Drd 9, Sor/Wiz 9)?
Does she gain domain spell slots for Level 1 through 9 or for Level 1 and 2 only?
Does she choose two additional Domains?
Do her level dependant domain powers work at caster level 3 or 17?

I would say that she casts spells as a lvl 17 cleric with access to the Air, Animal, Chaos, Good and Plant domains. With one domain spell slot per spell level. (KISS!)

Her caster level is 17 for all spells neither chaotic nor good (which are caster level 18). And she is able to turn and rebuke a wide variety of, uhm, beings.

I do not think she would gain access to any more domains, partly because I think she should be rather tightly bound to her domains, her being a celestial and all, and partly because it would be overkill.

(edit)
And of course she can cast Shapechange, it is one of her domain spells.
(/edit)

* I cannot stop imagining these divine beings as bagpipe-wielding and kilt-clad, and the superfluous "h" does nothing to mitigate that.

 

[StealthyMark]

My interpretation is slightly different.

As a standard ghaele, Shamira can prepare any spell in any number from the cleric list and from the Air, Animal, Chaos, Good and Plant domains. She could, for example prepare Chain Lightning (x2) and Greater Dispelling in her 6th-level spell slots. This is covered by "having access". (BTW, the wisdom score of a ghaele/trumpet archon is to low to cast 7th-level spells or higher! That's an error, IMO. But this is another story...)
She cannot, however, use any Domain powers. Domain powers are a class feature of a cleric. She cannot turn/rebuke undead, plants, earth or air creatures. She has no animal companions and her caster level is 14 for good/chaotic spells, too.
She also hasn't any domain spell slots. These are a cleric feature, too.

As an advanced ghaele Cleric 3, she chooses any two domains, according to her deity. She gains the associated domain powers. Level-dependent powers operate at level 3. She also turns undead as a 3rd-level cleric. And she can cast spontaneous cure spells, of course. She gains domain spell slots, to prepare her choosen domain spells.

I'm still not sure about the number of domain spell slots. I'm tempted to give her one spell slot for each spell level, because if a human cleric gets a divine PrC, he gains domain spell slots, too.

 

[StealthyMark]

Any opinions?

 

[Henrix]

No opinions really. I think your way is a fair bit more complicated than mine, which is why I prefer my own.

And I do not understand why you choose to interprete "A rakshasa casts spells as a 7th level sorcerer" and "Ghaeles in humanoid form can cast divine spells .... as 14th-level clerics" in such a wildly divergent manner.

Why not just treat them as born 14th level clerics, and add levels thereto. It seems so much simpler.