Foolishness CheckSometimes, even when players know better, characters still make foolish decisions because they would not know better. To simulate a character’s independence from the player, the GM may sometimes call for a Foolishness Check. These are typically made when the party has chosen a concrete plan of action, or when the GM feels one or more characters (based on their background or general motivation) may act against a player’s wishes.
Whenever a character fails a Foolishness Check, they must take an action which is: 1) contrary to the party’s wishes and/or detrimental to the party in some way; and 2) supported by the character’s background, motivations, fears, etc.
In d20 System (3.x, d20 Modern, & Pathfinder)
Each time a character succeeds at a Foolishness during a single adventure, his or her DC for future checks is increased by 2.
Whenever a player chooses to take a foolish action, his or her DC for future checks is decreased by 2 (minimum 8).
In 5th EditionA Foolishness Check is a Wisdom Saving Throw made against a DC of 15.
Each time a character succeeds at a Foolishness check he or she will have Disad-vantage on the next check made in the same adventure.
Whenever a player chooses to take a foolish action, they will have Advantage the next time they are asked to make a Foolishness Check.