Creature advancement qn: spellcasting

[hong]

A couatl is a 9HD monster that casts spells as a 9th level sorc. If I advance it to 27HD, what does that do to its spellcasting? 27th caster level sounds slightly over the top....

 

[HeavyG]

I don't think the rules cover this at all, but what I always do is give those types of monsters one level of spellcasting per +1 to their CR.

So since a normal 9HD couatl is CR 10 and a 27 HD couatl is CR 19, I'd say it casts as a (9+9) = 18th level cleric.

 

[Nellisir]

It's a design call. If you don't like caster level = HD, +1/CR works well. If it's a big dumb couatl, you could leave it at 9. Cha modifier x3.

(With a charisma of 17, a couatl might be restricted in it's spell selection at the highest levels)

Decide what level it should cast at, and justify it later.

Cheers
Nell.

 

[Grazzt]

I don't think the rules cover this at all, but what I always do is give those types of monsters one level of spellcasting per +1 to their CR.

So since a normal 9HD couatl is CR 10 and a 27 HD couatl is CR 19, I'd say it casts as a (9+9) = 18th level cleric.

Actually, the couatl's spellcasting level (and any other monster that casts/replicates spells) only increases if it adds class levels.

So, a 27 HD couatl still casts as a 9th-level sorcerer. If instead of advancing its HD, you add sorcerer levels, then its caster level increases. (Yes, I know normally a couatl advances by HD and not class levels, but you can add class levels to it instead of advancing it by HD. This is covered in the improving/advancing monsters section.)

This is covered, more or less, in the associated/non-associated class levels and advancing monsters stuff in the MM.

 

[Nellisir]

Actually, the couatl's spellcasting level (and any other monster that casts/replicates spells) only increases if it adds class levels.
...
This is covered, more or less, in the associated/non-associated class levels and advancing monsters stuff in the MM.

I don't see that. I see that if you add class levels to a monster with casting ability that ability increases (couatl 9 + sorc 2 = couatl sorc 11), but I don't see a statement that casting doesn't increase with HD. Do you have a clearer reference (page & paragraph, or column)?

Thanks
Nell.

 

[HeavyG]

Actually, the couatl's spellcasting level (and any other monster that casts/replicates spells) only increases if it adds class levels.

I know that's the rule*. I was just sharing how I do it.

I would do this because a CR 10 couatl needs its spellcasting to be a challenge and the CR 19 couatl will too, but 9th level spellcasting is just not going to cut it. But adding sorcerer levels makes sense too. I'd have to look at the two stat blocks to see which one is more appropriate to a CR 19 monster.


* Actually, it's more of a guideline than a rule, IMO. Advancing monsters is an art, not a science.

So, a 27 HD couatl still casts as a 9th-level sorcerer.

(Emphasis mine)

I wonder where I got that "cleric" thing from.

 

[Grazzt]

I don't see that. I see that if you add class levels to a monster with casting ability that ability increases (couatl 9 + sorc 2 = couatl sorc 11), but I don't see a statement that casting doesn't increase with HD. Do you have a clearer reference (page & paragraph, or column)?

Thanks
Nell.

Top of my head- nope. But I know Ive seen it, either in the MM or perhaps the D&D FAQ maybe. Can't recall at the moment. If I can dig it up, I'll post it.

 

[Nellisir]

Top of my head- nope. But I know Ive seen it, either in the MM or perhaps the D&D FAQ maybe. Can't recall at the moment. If I can dig it up, I'll post it.

Please do. I'm not trying to hassle you; I'd just like to know if there's an "official" rule or just an "understood" rule.

Didn't see it in the monster's section of the 7/2/04 Main FAQ, btw.

Thanks,
Nell.

 

[Voadam]

Advancing by HD only advances certain enumerated things. Spell casting is not one of those things, although special ability DCs are HD based.

INCREASING HIT DICE
As its Hit Dice increase, a creature’s attack bonuses and saving throw modifiers might improve. It gains more feats and skills, depending on its type, as shown on Table: Creature Improvement by Type.
Note that if a creature acquires a character class, it improves according to its class, not its type.

The couatl has spell casting as a 9th-level sorcerer, not as a sorcerer of level=HD.

Spells: A couatl casts spells as a 9th-level sorcerer.
It can choose its spells known from the sorcerer list, the cleric list, and from the lists for the Air, Good, and Law domains. The cleric spells and domain spells are considered arcane spells for a couatl, meaning that the creature does not need a divine focus to cast them.
Typical Spells Known (6/7/7/7/4; save DC 13 + spell level): 0—cure minor wounds, daze, disrupt undead, light, obscuring mist, ray of frost, read magic, resistance; 1st—endure elements, mage armor, protection from chaos, true strike, wind wall; 2nd—cure moderate wounds, eagle’s splendor, scorching ray, silence; 3rd—gaseous form, magic circle against evil, summon monster III; 4th— charm monster, freedom of movement.