Ok, so I am preparing to run my first campaign. When looking at CR, how does that relate to the level of the Enemy? If I am creating an evil cleric with a CR of 8, does that mean he is an 8th level Cleric. I know this is a noob question so thank you for your patience. Also is there a book or something for looking up CRs or is that just the bestiary?
Core Rulebook pages 397-399 cover this.
A creature that possesses class levels, but does not have any racial Hit Dice, is factored in as a creature with a CR equal to its class levels –1.
Thus, your 8th level cleric has a CR of 7.
- Gauss
Additionally, Bestiary pages 296-297 cover adding class levels to other creatures (with hit dice usually).
Short version there is that if you add a class level to a creature with hit dice the class level adds 1 to the CR unless it is a class that 'does not help' in which case only every 2 levels result in a +1 to the CR. There is a table that indicates which classes help which types of creature.
Example: a Troll is a combat creature thus adding 1 fighter level adds +1 to the CR. However, if you add 1 Sorcerer level to a troll it only adds 1/2 a CR (rounded down) to the Troll.
- Gauss
Creatures have CRs based on their abilities listed in their descriptions -- so yes, it's off to the bestiary for that.
However normal PC-races with PC classes have a CR equal to their level minus 1. (CR 1/2 at level 1).
Meanwhile normal PC-races with NPC classes (warrior, aristocrat, etc) have a CR equal to their level minus 2 (CR 1/3 at level 1).
Beyond that, if you start adding levels to things, you get to follow the rules in the bestiary, which I had quoted, but see that I've been ninja-ed above, so I'll just point upthread instead.
[Edit: Ninja-ed]
CR's are just guideposts, of course, so use your common sense when building challenges for your PC's.
In general, an NPC with PC class levels (fighter, bard, etc.) and character WBL is CR = level.
If the NPC is built with PC class levels and NPC WBL their CR = level minus 1.
If they are built with NPC class levels (adept, warrior, etc.) I forget but I think it is CR = level minus 2 (don't quote me on that, I don't generally use NPC levels).
Lots of things to consider when adding PC class levels to monsters. In addition to what Gauss wrote, you can only add the 2 levels per +1 CR of mismatched classes up to the original CR of the monster. After that it is +1 level for +1 CR (thanks to Ravingdork for setting me straight on that one).
Good luck!
Dosgamer, you are correct regarding the NPC class levels. Alternately, if applied to a creature with HD then it is 1/2 of class level = +1 CR.
I was just giving the short version out of the Bestiary.
- Gauss
Just some examples to illustrate the above...
NPC fighter 8 with npc wealth = CR 7
NPC fighter 8 with pc wealth = CR 8
NPC warrior 8 (I guess with npc wealth?) = CR 6
Troll = CR 5
Troll fighter 5 = CR 10
Troll cleric 5 = CR 7
Troll cleric 10 = CR 10 (after which adding more cleric levels becomes a 1 for 1 to CR)
Etc. Good luck!
Thanks everyone. Thus far I have just been using d20pfsrd.com I thought it had everything the CRB did. It would seem I was mistaken. I will have to invest in a CRB after all.
One thing doesn't make sense to me though. Say I have a 4 members of a party, with an APL of 5. According to this if they were to face a 6th level Cleric, or Fighter, etc. That would be a CR of 5 which would be an average challenge for them. Am I missing something here? The 5 man party would just destroy the single 6th level enemy.
A Challenge rating of 3 more than the APL should be an EPIC challenge, so if my 4 member party were to fight a single 9th level enemy that would be considered an epic challenge? My current gm just had my 4 man party fight a 10th level enemy with 3 level 3 guards...
Nope, you have a pretty good understanding.
An equal CR to APL should not to hard for the characters to overcome, but what it should do is deplete resources and cause some damage. As a GM, you put obstacles in the way, but not battles that are tough each time. Characters need to shine with easier battles and feel accomplished with harder battles.
Characters should be able to do about 4 of these in a day and not expect character death. When you increase the CR, you also increase the resources depleted and the chance of greater injury.
An CR equal to APL should cause a little worry, if played correctly. I see this being the largest hurdle to overcome. A barbarian will charge and do significant damage, possibly dropping a character near death, but this is not how a cleric or a rogue will fight. It is not how a group of goblins would fight either.
Know your creatures and their combat tactics and you will feel the strength of the CR system.
Use the environment and difficult terrain more. Lighting conditions are also forgotten often. You can build a CR 3 rogue goblin that can terrorize the party, but only if he is used correctly.
d20pfsrd is a great resource but if you require accuracy then you should definitely get a CRB pdf. At only 10$ it is a steal. - Gauss
That's because CR doesn't take into account the single biggest advantage the party has over an opponent, action economy. Unless the creature has some serious, even unusual, defenses, it will die in a round or two simply because it is 4 or 5 on 1.
For example, a shadow is a CR 3 creature. So is a 4th level fighter. However, that shadow is incorporeal, so even if the party goes after it with all they have, it takes much less damage. Plus, it can withdraw into walls. The fighter doesn't have these unusual defenses, just AC and hp.
I have found that adding an additional number of lower-level mooks equal to the CR of the big bad is good for giving it something of a challenge. A CR 5 cleric with 5 CR 1 bodyguards or so is a much more interesting fight.
CR also is very formulaic and doesn't take into account synergy between different classes or between classes and races, etc. For instance, Orc barbarians are much harder than they would appear, even at first level, thanks to ferocity, which basically gives them double hit points and lets them keep raging until they drop at -CON.
Seriously, if you want to mess your players up, throw an encounter that, by CR alone is level appropriate, of level 1 or 2 orc barbarians at them. If the orcs use even a modicum of appropriate tactics (i.e. not bunching up into fireball-sized groups) they can be incredibly difficult.
I think it's more that a lot of the incorporeal opponents seem to be woefully under ranked in CR...
And of course, CR is still an estimate. Change the environment slightly, supply more/less gear ... put in elements that can be use for or against the PCs, situation changes dramatically.
One thing doesn't make sense to me though. Say I have a 4 members of a party, with an APL of 5. According to this if they were to face a 6th level Cleric, or Fighter, etc. That would be a CR of 5 which would be an average challenge for them. Am I missing something here? The 5 man party would just destroy the single 6th level enemy.
A Challenge rating of 3 more than the APL should be an EPIC challenge, so if my 4 member party were to fight a single 9th level enemy that would be considered an epic challenge? My current gm just had my 4 man party fight a 10th level enemy with 3 level 3 guards...
As said above, it's a matter of the action economy -- a single creature without some serious special abilities suffers in comparison to a group (although some rare exceptions exist, like Hydrae and Ettins, in that they can do a lot more than a "normal" single creature)
It's also important to note that CRs are set expecting PCs that are a 15-point buy -- so "better" characters will, of course, have an easier time of things, as will a party with better-than-expected gear (and for similar reasons, considering a lower point-buy can be balanced with headbands and belts).
Further, an "average" fight is supposed to be one that the party wins (but drains resources, especially healing) - such that they can face four of those in a day and still be (more or less) expected to live.
To put that into perspective -- you can replace your single level 6 PC-character enemy with, instead, 2 level 4 PC-class characters (CR 3 each, 2 of them = CR 5) -- or a group of, say, 4 x Warrior 3 (a bargain at CR 1 each, x2 = CR 3, x2 = CR 5) -- and you see that you get a fight that the party will win, but not for free.
Now, getting into the challenge rating of +3 APL -- this is supposed to be an epic challenge -- and make the party actually work, and risk death. At CR 8, your 4-member party could be facing a party of 4 PCs of their own level (although, based on the rules, with slightly worse equipment), since a level 5 PC-class character is CR 4, and 4 of them = CR 8. [Of course, the bad guys probably have an advantage in that they can afford to nova at the party, so it balances..]
There are a few tricks that I use to make things work, here. For example:
Also, I do think that the core rulebook is a steal, and electronic is good because it lets you search (which is very helpful, the index isn't the best) -- I will also, however, point out that Paizo's PRD is organized the same way as the core rulebook, which makes it easy to find the section that discusses CR, which I've linked here