This picture was during the game of Zendo in which I was the "Master." Green stones indicate koans which have the Buddha-nature; red stones indicate those that don't. (The black card labeled "Zendo" is the koan that contains no pieces.) Can you figure out what the rule is?
As we've discussed before on this blog, dice superstitions are rampant in gaming circles. This "Dice Dungeon" is a prison used to punish dice that are rolling poorly. (It might actually work: after all, if you put poorly rolling dice in here, it is in fact true that when they come out, they will on average roll better in the future.)
On the other hand, when superstitions fail, one can always use more effective methods: