Halfling Luck

Halfling Luck is a passive feature in Baldur's Gate 3 that grants all halflings to reroll a die when it lands on a 1 for an Attack Roll, Ability Check, or Saving Throw.

Description

When you roll a 1 for an Attack roll, Ability check, or Saving throw, you can reroll the die and must use the new roll.

How to learn

Races:

• Character level 1: Halfling

(Character level is the sum of all class levels for a multi-classed character.)

Notes

• It is possible for the new roll to be another 1.
• As of patch 6, when rolling with advantage, the following rules apply:
  • If one die rolls a 1, it's re-rolled, and the higher of the two dice used.
  • If both dice roll a 1, they are both re-rolled, and the higher one used.
• The chance to hit displayed when hovering an attack on an enemy doesn't take into account Halfling Luck.
• Halfling Luck is particularly useful to avoid failures for ability checks and saving throws when the roll would only fail on a critical miss.
  • On a normal roll that succeeds on a 2 or more, Halfling Luck would reduce the chance to fail from 1/20 to 1/400.
  • On a roll with advantage that succeeds on a 2 or more, Halfling Luck would reduce the chance to fail from 1/400 to 1/160000, making it practically impossible to fail. With Karmic Dice active, it may be simply impossible to roll 4 critical failures in a row.
  • Traders can get all their easy to steal item stolen without fear of missing a single roll.
    • Be mindful that it can make your character  Heavily Encumbered which gives disadvantage on all ability checks, including further pickpocket attempts.
  • Stealth checks can get pretty much guaranteed to succeed.
  • Also useful to avoid Concentration getting interrupted too often by constitution save critical misses when taking low damage.

Math

Chances of succeeding a specific roll

See Advantage math section for comparison.

Chance of rolling a target number or above on 1d20 with Halfling Luck

Target on 1d20	Luck Normal Roll	Luck with Advantage	Luck with Disadvantage
1	100%	100%	100%
2	99.75%	99.9994%	99.5%
3	94.50%	99.7%	89.3%
4	89.25%	98.84%	79.66%
5	84%	97.44%	70.56%
6	78.75%	95.48%	62.02%
7	73.5%	92.98%	54.02%
8	68.25%	89.92%	46.58%
9	63%	86.31%	39.69%
10	57.75%	82.15%	33.35%
11	52.5%	77.44%	27.56%
12	47.25%	72.17%	22.33%
13	42%	66.36%	17.64%
14	36.75%	59.99%	13.51%
15	31.5%	53.08%	9.92%
16	26.25%	45.61%	6.89%
17	21%	37.59%	4.41%
18	15.75%	29.02%	2.48%
19	10.5%	19.9%	1.1%
20	5.25%	10.22%	0.28%

Chance to hit comparisons

On a normal roll, Halfling Luck multiplies the chance to hit by :

• 1.05 whatever the target roll is
  • This would be the most noticeable for a target roll of 2 which would add a flat 4.75% chance to hit or almost +1 on a d20.
  • For a target roll of 20 it would add a flat 0.25% chance to hit, which would be a critical strike.

On a roll with Advantage, Halfling Luck multiplies the chance to hit by :

• 1.003 for a target roll of 2 or a flat +0.25% chance to hit
• 1.01 for a target roll of 3 or a flat +0.70% chance to hit

...

• 1.03 for a target roll of 11 or a flat +2.44% chance to hit

...

• 1.05 for a target roll of 20 or a flat +0.47% chance to hit, which would be a critical strike.

On a roll with Disadvantage, Halfling Luck multiplies the chance to hit by :

• 1.10 whatever the target roll is
  • This would be the most noticeable for a target roll of 2 which would add a flat 9.25% chance to hit or almost +2 on a d20.
  • For a target roll of 20 it would add a flat 0.03% chance to hit, which would be a critical strike.

Chance to fail comparisons

On a normal roll, Halfling Luck divides the chance to fail by :

• 20 for a target roll of 2
• 1.82 for a target roll of 3
• 1.40 for a target roll of 4

...

• 1.003 for a target roll of 20

On a roll with Advantage, Halfling Luck divides the chance to fail by :

• 400 for a target roll of 2
• 3.31 for a target roll of 3
• 1.95 for a target roll of 4

...

• 1.01 for a target roll of 20

On a roll with Disadvantage, Halfling Luck divides the chance to fail by :

• 19.52 for a target roll of 2
• 1.78 for a target roll of 3
• 1.36 for a target roll of 4

...

• 1.0003 for a target roll of 20

External Links

• Advantage and Halfling luck calculation by Kalaeman