Some House Rules about Luck
In the Dungeon Crawl Classics RPG, character Luck is intended to go up and down based upon the circumstances of play. In general, Luck goes up due to rewards given by the judge, and goes down as it is used up by the players to modify rolls. The judge can also penalize Luck, but, because players rely on it, and it is generally lost forever when spent, bonuses tend to outweigh penalties. This is true even in the official published adventures, where Luck penalties tend to be temporary where they exist at all.
The thief and halfling classes, however, regain spent Luck, which means that, if they gain bonuses as do the rest of the PCs, pretty soon their Luck will be absolutely phenomenal. Unless the judge sets a cap, the player can have Luck that reaches well beyond the 18-20 range.
What to do?
Permanently Burning Luck – The Carrot
In my game, it is now a house rule that a thief who permanently burns a point of Luck automatically gains the maximum roll on his Luck Die.
A halfling who permanently burns a point of Luck gains a +3, rather than a +2, bonus to the roll.
Luck is Fickle – The Cattle Prod
In my game, it is now a house rule that any character whose permanent Luck is 16+ or 5- at the end of a game session must roll 1d20 and compare the result against his permanent Luck. Permanent Luck is the Luck score that most characters have, and that a thief or halfling can recover Luck to reach.
If the result of the d20 roll is greater than the character’s Luck, supernatural forces help the character, granting a point of Luck in game terms. The character gains a point of Luck.
But, if the d20 roll is under the character’s Luck, the character loses a point of Luck. Supernatural forces, Karma, or the perversity of the cosmos simply work against him.
If the character rolls exactly his Luck score, there is no change if his Luck is between 8 and 19, but if his Luck is 7 or less, he gains 2 points of Luck. If he Luck is 20, he loses 2 points of Luck.
A character whose Luck is between 6 and 15 at the end of a game session need not roll, but can choose to do so if the player wishes. In any event, only the raw, unmodified die roll is considered.