CR Estimation Table (DnD Guideline)
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 How to Use These Tables
This table exists for two purposes:
- To aid a creature designer in determining the CR of a creature.
- To guide a creature designer in designing a creature of any given CR.
Judging the CR of a creature is a complicated task. It is one part science, one part art, and one part experience. This table helps you with the science part of that equation. It is up to the creature designer to make judgments based on this information.
This table assumes the following about a creature:
- The creature has 2-3 attack, both primary and secondary
- The creature has one interesting ability that gets used during an encounter.
- The creature has a strong melee orientation.
Factors which vary from these base assumptions will adjust CR.
 Character AC and Creature Attack Bonus
In order to correctly figure the attack bonus of a creature, you must first understand the realistic armor class of a character. Using information from the Magic Item Compendium for character equipment, tank style characters should have armor classes in the ranges listed below. The table itself is "rough" as I smoothed no numbers out from the raw calculations.
Heavy armor assumes that a character beings with banded armor, then progresses to magic field plate by 7th. Medium armor assumes that the character begins with chain, and advances to mithral plate by 7th.
Note that the armor calculations assume that you are maximizing your defense as much as possible with commonly available, permanent items.
| Heavy Armor
| Heavy Armor
+ Heavy Shield
|Medium Armor|| Creature
Heavy Armor and Tower Shield : The armor class of a fighter in heavy armor, with a tower shield, fairly optimized for defense.
Heavy Armor and Heavy Shield : The armor class of a combatant in heavy armor, with a heavy shield, fairly optimized for defense.
Medium Armor : The armor class of a character in medium armor, fairly optimized for defense, but using no shield.
Attack Bonus : The effective attack needed to hit an optimized heavy fighter, with a tower shield, 75% of the time.
Fudge Factor : A number added to the Attack Bonus to make it come out correctly. This accounts for the increasingly powerful defensive spells being cast during combat.
The table above fairly approximates what a creature can do.
You must also assign a basic role to your creature: alpha, melee, melee and kicker, or magic.
Alpha: Alpha creatures are clearly better than other creatures at their category. These are reserved for the creatures who must make a better than average showing for their level, such as a dragon. Such creatures usually have a +2 to a +8 above their normal counterparts.
Melee: Creatures who attack entirely with melee, usually doing one thing well. Creatures with multiattack reduce their penalties from this number. The more attacks that a creature has, the larger the negative. -2 for 2-3 attacks, -4 to -5 for 4-5 attack, and -6 to -7 for hydra/octopus attacks.
Melee + Kicker: This creature has a good effect in addition to melee, and that effect supports the creature in melee. Its attack bonus should be -3 to -5. They hit less often, but when they do hit, bad things can happen.
Magic: This creature relies on magic during melee. This creature should have a -5 to -7 to its attack bonus.
 Character Attack and Creature AC Table
A character's attack corresponds to a creature's armor class. For this table to work correctly, we must understand both a 1/1 BAB attack and a 3/4 BAB attack. If we base AC on a 1/1 BAB, 3/4 attack characters will become increasingly useless, while 1/1 BAB will not have any reason to choose Power Attack or Combat Expertise. Therefore, we must base a creature's armor class on the expected abilities of a 3/4 BAB character. A 3/4 BAB character will be able to hit a creature 50% of the time, which is their effective attack value +8.
Full BAB does not account for Rage, Weapon Focus, or any other type of bonus to attack.
|Level||Scheduled Bonuses||BAB Full||BAB 3/4||Creature AC|
Level: This is the character level and creature CR.
Scheduled Bonuses: These are bonuses from magic weapons, attribute increases and enhancements, and tomes.
Full BAB: This is the reliable attack bonus for a character with full BAB progression.
3/4 BAB: This is the reliable attack bonus for a character with a 3/4 BAB progression.
Creature AC: This is 3/4 BAB + 8.
Creature AC strongly follows 3/4 BAB. By design, primary attacks from 3/4 BAB characters are designed to hit 2/3 of the time.
 Character Save and Creature Effect
 Character Effect and Creature Save
This is a first attempt at this table. It does not quite work. Creature saves appear to be mildly randomized, as other factors were more important in developing a creature. As the designers fudge the creatures, the saves fell victim to their method of fudging by using stats.
 Dragon Estimation Table
Dragons are among the most well-defined of all creatures. We have examples from their youngest to oldest ages, spanning the entire breadth of the CR chart. For their damage, see the True Dragon.