Advancing Monsters / Advancing Caster Level

[Garnfellow]

Hello, All!

So creatures with spell-like abilities normally have a caster level associated with those abilities, in order to resolve things like dispel attempts and level-based effects. By default this caster level is equal to the creature's HD, but sometimes a specific caster level is designated.

In situations where the caster level is designated, is there any rhyme or reason to what level is assigned? It seems to be associated with spell level, but I can't pin a consistent pattern down. And what happens when you advance the monster?

For example, a devourer (12 HD) uses its spell-like abilities as an 18th level sorcerer. Where did the 18 come from? And what happens to the caster level when I advance the devourer to 24 HD? Stay the same (18)? Equal the devourer's total HD (24)? Equal the original caster level + 1/each new HD (30)?

Any help is most appreciated!

 

[MissHappen]

Spell casting? (c-a-s-t-i-n-g)

Hey there.

As far as I can tell, assigning a caster level to a creature with spell-like abilities seems to follow the same guidelines as the 'natural armor' rule, which is to say.... whatever you pretty much want it to be.

Where does the Intellect Devourer's level 18 casting come from? Well, probably a lot of brain matter, I'd guess.

As to advancing... that's a good question. If the assignation of caster level is as arbitrary as natural armor, then hey, whatever works for you, so long as you play it carefully and don't get excessive. For myself, I'd probably come up with a set number for each range of advancement, preferably proportional to the original ratio of spell caster levels to HD.


-MsM

 

[BOZ]

MsM! long time no see

i'll agree. there doesn't appear to be any rhyme or reason as to how caster levels are assigned. sometimes it follows the creature's HD, but as often as not it's set at whatever the author needs it to be at.

 

[Knight Otu]

There are almost no indications for those things in the current Monster Manual. Some of the newer products show instances where caster level does scale with creature HD/level. The one instance I know caster level doesn't scale is the spell-like abilities of gnomes.

 

[Garnfellow]

Well, you good folks have confirmed my suspicions. Maybe the 3.5 MM will have more explicit guidelines for assigning and adjusting the caster level as the monster advances.

As far as what to do with the advanced devourer, I think I'm going to follow the lead of how SR progresses -- +1 for every additional CR. So a 12 HD devourer (11 CR) advanced to 24 HD (13 CR) increases its caster level from 18 to 20.

(By the way, the only place I've ever found this SR rule is in the MMII, buried as a note within the example of advancing a dune stalker. Does this little nugget appear anywhere else?)

 

[MissHappen]

hmmm

Hi, Boz! I promise I'll visit more often now that I have a bit more time to type. And hello again, Otu.

Good eye, Garnfellow. I missed the bit about the Dune Stalker advancement... off the top of my head, I don't recall seeing anything anywhere else that seemed related.

I suspect that if 3.5 comes up with a ruling, it will be an open-ended one. Like the 'natural armor' bonus, it would be hard to come up with a concrete method of determining casting level via HD that doesn't impede with free-wheeling monster design. Say, for example, you want something sprite-ly and 2-HDish but with surprisingly powerful spells (how about a Sleep spell at 18th level?).
Well, even if they don't, I hope they don't take it personally when some of us still fudge the numbers anyway.

-MsM