Monstrous Spellcasters and the SRD

[Garnfellow]

Sometimes a creature can cast arcane or divine spells just as a member of a spellcasting class can (and can activate magic items accordingly). . . . A spellcasting creature is not actually a member of a class unless its entry says so, and it does not gain any class abilities.

As I have always understood it, if such a creature took levels in the same class as which it casts spells, those class levels stack with its innate spellcasting ability. A nymph, for example, casts divine spells as a 7th-level druid. If she takes 3 levels of druid, those levels stack with her spells ability. So a nymph druid 3 casts spells as a 10th-level druid.

But when I checked the SRD to confirm my understanding, the only thing I could find is this oblique statement under “Improving Monsters”:

A spellcasting class is an associated class for a creature that already has the ability to cast spells as a character of the class in question, since the monster’s levels in the spellcasting class stack with its innate spellcasting ability.

Is this rule about spellcasting levels stacking stated more clearly or directly anywhere else in the SRD?

 

[Knight Otu]

Rakshasa. Though for some odd reason, it also empowers the familiar.

Also note that the first quote you provide is in no way contradictory to your (correct) understanding. It just notes that the creature does not gain any other benefits of that class, and is treated as lower level for those ability.

 

[Shade]

Some monsters (like the phaerimm) specifically state it, like this:

A phaerimm’s favored class is sorcerer. Its sorcerer levels stack with its base spellcasting ability for the purpose of determining spells known, spells per day, and other effects dependent on caster level. A phaerimm character likewise uses the sum of its racial spellcasting levels and appropriate class levels to determine the abilities of its familiar, though it cannot acquire a familiar until it takes at least one level in the sorcerer class.

Others don't.

To me, it makes no sense for a creature to cast as a 3rd-level sorcerer and as a 1st-level sorcerer separately, rather than simply casting as a 4th-level sorcerer, so I always rule it this way.

 

[Garnfellow]

Rakshasa. Though for some odd reason, it also empowers the familiar.

Also note that the first quote you provide is in no way contradictory to your (correct) understanding. It just notes that the creature does not gain any other benefits of that class, and is treated as lower level for those ability.

Good eyes on the rakshasa. So it sounds like this stacking rule isn't directly stated within the SRD in any of the places one would expect it to be stated -- like in the Monsters as Characters or Improving Monsters sections.