Probability Based Ability Point System
Standard Rules
You start with a 12 for each ability score. By selecting scores lower than 12, you can gain points to increase other abilities. As long as the total ability score point cost remains 0 (or less), you are fine. The cost of each score is shown on the Ability Score Point Cost table.
For example, if you choose to set your Intelligence to 10, that is -4, or 4 extra points. You could then set your Wisdom and Constitution to 14 each. Since a 14 costs 2 points, -4 + 2 + 2 = 0.
This method of determining ability scores enables you to take six 12's as the average. Alternatively you can max out two abilities with 9, 9, 10, 12, 16, 16; or max out three abilities with 9, 10, 10, 15, 15, 15.
Ability Score Point Cost
| Score | Cost |
|---|---|
| 9 | -7 |
| 10 | -4 |
| 11 | -1 |
| 12 | 0 |
| 13 | 1 |
| 14 | 2 |
| 15 | 5 |
| 16 | 9 |
Variant: The Full Table
| Score | Cost |
|---|---|
| 4 | -16 |
| 5 | -15 |
| 6 | -14 |
| 7 | -12 |
| 8 | -10 |
| 9 | -7 |
| 10 | -4 |
| 11 | -1 |
| 12 | 0 |
| 13 | 1 |
| 14 | 2 |
| 15 | 5 |
| 16 | 9 |
| 17 | 13 |
| 18 | 16 |
The full Ability Score Point Cost table is shown above. You DM may allow you to use the full table for generating ability scores, or they may limit the table to a different range than 9-16.
Notes
The point costs in this table are based on the probabilities of rolling the given scores using the standard 4d6 keep 3 method.
The standard array of ability scores (8, 10, 12, 13, 14, 15) costs -6 points under this system. The average roll of six abilities (9, 10, 12, 13, 14, 16) costs 1 point under this system.