Monsters w/ Class Levels and CR

[Herabec]

So, was just wondering... How should I go about handling the CR of monsters with class levels? For example: an Adult Black Dragon, CR 11. However, because I want him to have a few more skill points and evasion, I give him two levels of Rogue.

This gave him +1 BaB, +3 Reflex saves, Trapfinding and Evasion and 10 HP.

...

Is that really worth the CR +2 it tacks onto him?

Of course, this also leads the whole question of whether or not PC classes are really worth their level=CR rating at all.

What are the Playground's opinions?

[Salanmander]

I believe the "improving monsters" section of the monster manual covers this. In short, if you're adding "associated" class levels (levels that directly improve the monster's primary schtick) the CR goes up by one per level. If you are adding "non associated" class levels, the CR goes up by 1/2 per level (until you get to some limit, like the monster's original CR in class levels or something).

[Herabec]

I believe the "improving monsters" section of the monster manual covers this. In short, if you're adding "associated" class levels (levels that directly improve the monster's primary schtick) the CR goes up by one per level. If you are adding "non associated" class levels, the CR goes up by 1/2 per level (until you get to some limit, like the monster's original CR in class levels or something).

Ah. *headdesks* I completely forgot about that.

Well, thank you for the reminder. I'll go take that into consideration. Sounds much more reasonable than a flat +1 CR per level.

[GoodbyeSoberDay]

Note that this rule of thumb really doesn't work well in specific cases. A lot of times you're going to have to eyeball it unless you want to TPK a low level group with a bunch of CR 1 Kobold Adept 4s.

[DeAnno]

There are cases where adding optimized class levels to monsters or templates to optimized class levels results in seriously under CRed creatures. I've fought against a trio of homebrew CR 16s built this way that could TPK most nonoptimized level 20 parties (though I think they had built in gear too, which is a whole extra matter).

[Keld Denar]

Black Dragons are more "sneaky" dragons, as evidenced by their skills and SLAs. Thus, "sneaky" type classes would probably be associated for them.

Thus, yes, +2 levels of Rogue would result in a +2 CR bump. Keep in mind that the extra HD will increase its BW and Fear DCs by 1 (since DCs are 10 + 1/2 HD + ability), and might give the dragon an extra feat or ability boost.

[Knaight]

Note that this rule of thumb really doesn't work well in specific cases. A lot of times you're going to have to eyeball it unless you want to TPK a low level group with a bunch of CR 1 Kobold Adept 4s.

As a rule one would just look at the Adept 4 as the deciding factor. Much like an Ogre (CR 3) who is also a level 8 Sorcerer would be looked at as a sorcerer, with the Ogre "levels" looked at as non associated.

[Herabec]

Black Dragons are more "sneaky" dragons, as evidenced by their skills and SLAs. Thus, "sneaky" type classes would probably be associated for them.

Thus, yes, +2 levels of Rogue would result in a +2 CR bump. Keep in mind that the extra HD will increase its BW and Fear DCs by 1 (since DCs are 10 + 1/2 HD + ability), and might give the dragon an extra feat or ability boost.

Hrm... You've got a point there.

Though, when it comes to the Fear and BW DCs, wouldn't those be based solely off it's Dragon HD and not from any class levels it may possess?

[ImperatorK]

That depends if you're interpreting "1/2 dragons HD" as just HD (which class levels are also) or as "dragon HD". I would go with the later.

[Glimbur]

This gave him +1 BaB, +3 Reflex saves, Trapfinding and Evasion and 10 HP.

...

Is that really worth the CR +2 it tacks onto him?

Of course, this also leads the whole question of whether or not PC classes are really worth their level=CR rating at all.

What are the Playground's opinions?

Don't forget the sneak attack. Dragons are basically blenders anyway, so if you can proc sneak attack it's another 3.5 damage per swing, on average. That's worth something.

[Keld Denar]

Though, when it comes to the Fear and BW DCs, wouldn't those be based solely off it's Dragon HD and not from any class levels it may possess?

HD are HD. DC is 10 + 1/2 HD + ability (Con in the case of BW). It doesn't matter if they are dragon HD or class level HD. If you give a ghost a bunch of character levels, it's DCs go up. Why would a dragon be any different?

[Runestar]

HD are HD. DC is 10 + 1/2 HD + ability (Con in the case of BW). It doesn't matter if they are dragon HD or class level HD. If you give a ghost a bunch of character levels, it's DCs go up. Why would a dragon be any different?

Because the dragon's entry in the MM explicitly states their abilities as being based off racial HD. So class lvs would not improve their DCs.

Rogue won't really add much, IMO. I suppose if you could set up the fight to really take advantage of its sneak attack (say craven for another +HD to SA damage?) Otherwise, I can certainly see more bang for your buck if you added another flat 3 racial HD, or other class lvs like warblade/swordsage.

[TroubleBrewing]

Because the dragon's entry in the MM explicitly states their abilities as being based off racial HD. So class lvs would not improve their DCs.

Wrong, wrong, wrong. "The save DC against a breath weapon is 10 + 1/2 dragon's HD + dragon's Con modifier."

It says nothing about being keyed to RHD.

[Glimbur]

PC class levels entitle a monster to have the elite array, but dragons might get that anyway due to, you know, dragon.

[Runestar]

Wrong, wrong, wrong. "The save DC against a breath weapon is 10 + 1/2 dragon's HD + dragon's Con modifier."

It says nothing about being keyed to RHD.

Or just look at the stats of just about every printed dragon with class lvs, their dcs never factor in class lvs. Dragons of faerun and wyrms of the north are good places to start. :)

[Taelas]

I have also never seen a monster with more than 4 RHD get an ability boost out of the deal, despite it being a specific benefit from having HD divisible by 4.

[Runestar]

I have also never seen a monster with more than 4 RHD get an ability boost out of the deal, despite it being a specific benefit from having HD divisible by 4.
It's already factored into their stats; the extra stat points only apply if you are manually advancing a monster.

[Taelas]

No, they aren't. They say they are, but this is simply to avoid having to adjust it for every monster with RHD in the book. Most monster stat blocks have either a mix of 10s and 11s (usually three of each, but it varies), the elite array, or nonelite array, plus racial ability modifiers.

They also do not always include them when advancing monsters. Check the example Otyugh on page 292; it should have gotten two ability increases from advancing hit dice, but the only changes in ability scores come from size. This is the example meant to illustrate the concept of advancing monsters.

They do include it in the Elder Black Pudding on page 201; it has higher Str and Con than the non-advanced Black Pudding next to it, some of which is from size, the rest of which is from ability score increases due to HD (namely, +1 Str, +2 Con). This is the only example of a single creature with two stat blocks, one of which is the advanced form of the other through nothing but increased hit dice, where the statistics are completely accurate that I am aware of in the Monster Manual.

[Herabec]

Note to self: An adult black dragon with an elite array and evasion is a very, very nasty foe.

And a slayer of Clericzillas.

*cough*

On a more constructive note, I like the idea of limiting a dragon's ability DCs as focused on their Draconic HD rather than their total HD. My reasoning is basically due to Age Categories; the more dragon HD it's got, the older it is, and so the DC's against it's abilities should also be higher like everything else.

But PC levels are trained abilities, and shouldn't strengthen the powers a dragon develops due to age and maturity.

...though that likely doesn't make sense. That's my way of thinking about it.

[DeAnno]

They also do not always include them when advancing monsters. Check the example Otyugh on page 292; it should have gotten two ability increases from advancing hit dice, but the only changes in ability scores come from size. This is the example meant to illustrate the concept of advancing monsters.


Do as the monster manuals say, not as they do :smallsmile:

For my part I've always treated all HD keyed saves as being 1/2 total HD unless they specifically say otherwise. Even if such weighty tomes as Dragons of Faerun have counterexamples, I would rather trust the letter of the RAW in the MM.

[Divide by Zero]

The descriptions for breath weapon (http://www.d20srd.org/srd/specialAbilities.htm#breathWeapon) and frightful presence (http://www.d20srd.org/srd/specialAbilities.htm#frightfulPresence) both explicitly say racial HD.