For creature stat creation, this spreadsheet is a helpful resource to calculate a creature’s stats based on an intended challenge rating.
UNDER CONSTRUCTION…
Basics to Challenge Rating (CR)
A basic break down of a creatures’ challenge rating is thus:
Challenge Rating = [Defensive Challenge Rating + Offensive Challenge Rating]/2
In other words, the CR is the average of the Defensive CR and the Offensive CR.
Defensive CR = CR determined by Hit Points adjusted for by Armor Class.
Offensive CR = CR determined by Damage per Round adjusted for by either Attack Bonus and/or Save DC.
Now, what does that all mean?
Defensive CR: Find the Hit Points of the creature on the Hit Points column below. Then, from that row, go left to the CR column. The table cell you land on is your starting Defensive CR. Now, in the same row, go right to the Armor Class column, and the cell you land in is the average AC for that CR. Check your creature’s AC. For every two points above or below the average AC that your creature’s AC is, increase or decrease the Defensive CR by one.
Example: A creature has 140 Hit Points and an AC of 14. The Hit Points place the Defensive CR at 5. A creature with a CR of 5 has an average AC of 17. The actual AC is 3 lower from the average AC. So 3/2 = 1.5, rounded down to 1. This means that the Defensive CR needs to be lowered by 1 to a final Defensive CR of 4.
Offensive CR: Similar to Defensive CR, find the Damage per Round of the creature on the Damage Per Round column below.
Note, Damage per Round is calculated as the average damage for a round, assuming two successful hits per round. The average damage for each die is listed below.
| Damage Die | Average Value |
|---|---|
| d4 | 2.5 |
| d6 | 3.5 |
| d8 | 4.5 |
| d10 | 5.5 |
| d12 | 6.5 |
- Example: A creature deals 3d6+3 per successful hit, so each hit is (3×3.5)+3=13.5, rounded down to 13 damage. Then, assuming two successful hits in a round, double that to 26.
Then, from that row, go left to the CR column. The table cell you land on is your starting Offensive CR. Now, in the same row, go right to either the Attack Bonus or Save DC column. This is determined by if the damage was caused with an Attack Bonus or a Save DC. The cell you land in is the average Attack Bonus or Save DC for that CR. Check your creature’s Attack Bonus or Save DC. For every two points above or below the average Attack Bonus or Save DC that your creature’s Attack Bonus or Save DC is, increase or decrease the Offensive CR by one.
Example: A creature deals an average of 26 Damage per Round with an Attack Bonus of +10. The Damage per Round places the Offensive CR at 3. A creature with a CR of 3 has an average Attack Bonus of +6. The actual Attack Bonus is 4 higher from the average Attack Bonus. So 4/2 = 2. This means that the Offensive CR needs to be increased by 2 to a final Offensive CR of 5.
Challenge Rating: Once you have the Defensive and Offensive Challenge Ratings, take the average. In other words, add them together and divide by two. Frequently, this results in a number with a decimal, in which case, round down.
Example: The creature has a Defensive CR of 4 and an Offensive CR of 5, so the actual CR is (4+5)/2 = 4.5. Rounded down, this is a CR 4 creature.
| CR | Proficiency Score | Hit Points | Armor Class | Damage per Round | Attack Bonus | Save DC |
| 1/8 | +0 | 0-35 | 11 | 0-1 | +1 | 11 |
| 1/4 | +0 | 36-55 | 12 | 2-4 | +2 | 12 |
| 1/2 | +1 | 56-70 | 13 | 5-8 | +3 | 13 |
| 1 | +2 | 71-85 | 14-15 | 9-14 | +4 | 14 |
| 2 | +3 | 86-100 | 16 | 15-20 | +5 | 15 |
| 3 | +4 | 101-115 | 17 | 21-26 | +6 | 16 |
| 4 | +5 | 116-130 | 18-19 | 27-32 | +7 | 17 |
| 5 | +6 | 131-145 | 20 | 33-38 | +8 | 18 |
| 6 | +7 | 146-160 | 21 | 39-44 | +9 | 19 |
| 7 | +8 | 161-175 | 22-23 | 45-50 | +10 | 20 |
| 8 | +9 | 176-190 | 24 | 51-56 | +11 | 21 |
| 9 | +10 | 191-205 | 25-26 | 57-62 | +12 | 22 |
| 10 | +11 | 206-220 | 27 | 63-68 | +13 | 23 |
| 11 | +12 | 221-235 | 28-29 | 69-74 | +14 | 24 |
| 12 | +13 | 236-250 | 30 | 75-80 | +15 | 25 |
| 13 | +14 | 251-265 | 31-32 | 81-86 | +16 | 26 |
| 14 | +15 | 266-280 | 33 | 87-92 | +17 | 27 |
| 15 | +16 | 281-295 | 34-35 | 93-98 | +18 | 28 |
| 16 | +17 | 296-310 | 36 | 99-104 | +19 | 29 |
| 17 | +18 | 311-325 | 37-38 | 105-110 | +20 | 30 |
| 18 | +19 | 326-340 | 39 | 111-116 | +21 | 31 |
| 19 | +20 | 341-355 | 40-41 | 117-122 | +22 | 32 |
| 20 | +21 | 356-400 | 42-43 | 123-140 | +23 | 33 |
| 21 | +22 | 401-445 | 44-45 | 141-158 | +24 | 34 |
| 22 | +23 | 446-490 | 46-47 | 159-176 | +25 | 35 |
| 23 | +24 | 491-535 | 48-49 | 177-194 | +26 | 36 |
| 24 | +25 | 536-580 | 50-51 | 195-212 | +27 | 37 |
| 25 | +26 | 581-625 | 52-53 | 213-230 | +28 | 38 |
| 26 | +27 | 626-670 | 54-55 | 231-248 | +29 | 39 |
| 27 | +28 | 671-715 | 56-57 | 249-266 | +30 | 40 |
| 28 | +29 | 716-760 | 58-59 | 267-284 | +31 | 41 |
| 29 | +30 | 761-805 | 60-62 | 285-302 | +32 | 42 |
| 30 | +31 | 806-850 | 63 or more | 303-320 | +33 | 43 |
Multiple Attacks
What if the creature has multiple types of attacks? Assume the creature deals damage with two successful hits over three rounds. Select a combination of attacks that makes the most sense. Find the average for each round and then average of those three rounds. This is your Damage Per Round score to use.
Abilities and Effective Values – UNDER CONSTRUCTION
Now some abilities are very powerful. These are dealt with through Effective Values, aka Effective Hit Points, Effective Armor Class, Effective Damage per Round, Effective Attack Bonus, and Effective Save DC. These abilities change the value used to determine CR but do not change the actual values of the creature.
Example: the creature from before also can fly. Flight increases the Effective AC by 4, to a total Effective AC of 18. The Hit Points still place the Defensive CR at 5. A creature with a CR of 5 has an average AC of 17. The actual AC is 1 higher from the average AC. So 1/2 = 0.5, rounded down to 0. This means that the Defensive CR changes from 4 (where the AC was much lower) to 5. With the Defensive CR of 5 and Offensive CR of 5, the CR is averaged to 5. This is an increase from the original result of CR 4.