Function of CR

The higher the challenge rating (CR) number, the more powerful the enemy. Commonly four characters of a certain level are able to defeat one creature with a CR equal to the average level of the characters with a moderate amount of difficulty.

It can be viewed by examining the creature.

  • Impossible (purple): 5 or more levels higher
  • Overpowering (red): 3 or 4 levels higher
  • Very Difficult (orange): 1 or 2 levels higher
  • Challenging (yellow): same or 1 level lower
  • Moderate (blue): 2 or 3 levels lower
  • Easy (green): 4 or 5 levels lower
  • Effortless (white): 6 or more levels lower

It should be noted that these distinctions can become largely irrelevant on some local vault servers, simply because a player can edit his character at will and/or give their character items and weapons that far surpass the damage rating system. This is also true for any server that allows a player to reach a high level because the challenge depends more on the equipment and character build than truly on their level.

CR Formula

The Challenge Rating of a Creature is calculated using many sources. Below is the step-by-step procedure for calculating Challenge Rating.

Add up all the following:

HD * 0.15

(Natural AC bonus) * 0.1

[ (Inventory Value) / (HD * 20000 + 100000) ] * 0.2 * HD

[ (Total HP) / (Average HP) ] * 0.2 * HD * (Walk Rate) / (Standard Walk Rate)

[ (Total of all Ability Scores) / (HD + 50) ] * 0.1 * HD

[ (Total Special Ability Levels) / { (HD * (HD + 1) ) + (HD * 5 ) } ] * 0.15 * HD

[ (Total Spell Levels) / { (HD * (HD + 1) ) } ] * 0.15 * HD

[ ((Bonus Saves) + (Base Saves)) / (Base Saves) ] * 0.15 * HD

[ (Total Feat CR Values) / (HD * 0.5 + 7) ] * 0.1 * HD

then multiply the total sum by the racial challenge rating modifer, the CRModifier value from racialtypes.2da, using the creature's race as an index into the 2da. The resulting value is the Additive CR.

Terms Used Explaination

HD = Hit Dice = total number of levels the creature has in all of its classes.

Natural AC Bonus

Inventory Value = total value of all items in the Creature's inventory, not counting items equipped in the creature weapon slots or the creature hide slot. See Section 4.4 of the Items document for how to calculate item cost.

Total HP = total hit points, not including bonuses from constitution or feats.

Average HP = average hit points based on average hit point dice rolls for each class. For example, a creature having classes Outsider 7/Fighter 3 (d8 and d10 hit dice, respectively) would have Average HP = [7 * (8 + 1)/2] + [3 * (10+1)/2] = 7*4.5 + 3*5.5.

Walk Rate = creature's walk rate from the WALKRATE column of creaturespeed.2da, using the creature's WalkRate GFF Field as the 2da row index.

Standard Walk Rate = The WALKRATE column value for row 0 in creaturespeed.2da, which corresponds to player characters' movement rate.

Total of all Ability Scores = total of all ability scores, before any modifications due to race, feats, or equipped items.

Total Special Ability Levels = total levels in all special abilities in the creature's SpecAbilityList GFF List. For each spell in the special ability list, get its Innate value from spells.2da, and add that to the total special ability levels.

Total Spell Levels = total levels of all spells in all the spell lists in all the creature's classes. The level of a spell is taken as its Innate value from spells.2da. If the Innate level is 0, then count it as 0.5.

Bonus Saves = total of the creature's fortbonus, refbonus, and willbonus GFF Fields.

Total Feat CR Values = total CR Values of all feats that the creature has. The CR Value of a feat is its value under the CRValue column in feat.2da" (bioware,

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