The Dungeons of Runa
Deck of Duds
A deck of cards that are more than they appear.
Spellcaster Level 20
Spell Resistance: 20
The deck of duds are a spiritual game that only spellcasters are able to play. To anyone who picks up the cards they appear to have no faces, numbers, etc.
If someone casts detect magic they will realize these cards are more than they appear. If a spellcaster puts magic into the cards then they will reveal themselves and the game will begin. Once the game has begun there is no backing out. The spellcaster and anyone near him must play the game or go against their spiritual self.
If anyone attempts to leave the game they must roll a will save and fortitude save. If the will save is failed they can not leave the table. If successful they roll the fortitude save. If they fail the fortitude save they experience a randomized curse rolled off of a D20. The effects can range from being turned purple to your class being changed at a high or low called D% chance of being permanent.