Foolishness Check

While running a "summer slasher flick" one-off adventure for d20 Modern, I wanted to make sure that the characters still acted like the idiots we normally see in horror films--particularly since all my players were horror fans, and certainly knew better.  Below is the mechanic I settled on.  It added a sense of plausibility to the genre, and the players loved it.

Since the trope ultimately has its origins in gothic literature, the Foolishness Check would also be appropriate in a gothic fantasy setting/story.  It may now, however, be used as frequently as in a modern horror game with victim-style characters.  Since that slasher game, I have kept the mechanic in my back pocket to use whenever I feel the need.

Foolishness Check

Sometimes, 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.

At any time, whether the GM calls for a check or not, a player may choose for his or her character to take a foolish action that meets the criteria above. When doing so, the character gains a benefit on the next Foolishness Check (see below).

In d20 System (3.x, d20 Modern, & Pathfinder)

A Foolishness Check is a Will Save made against a starting DC of 10.

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 Edition

A 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.