Reversed Tarot Cards are a popular suggestion. Everyone gives this a whack at some point, so here's my try. It is a pretty reasonable idea, and captures another element of the source inspiration. (Even if it against the Unwritten Rules.)
Most implementations of this idea just simply list 22 new card effects, generally related to the original effect in some way. I'm going to attempt to keep things a little bit fresh, by instituting a slightly different manner of use.
Reversed Tarot Cards in divination typically represent the original interpretation being blocked somehow, and generally the person being read is responsible for but unaware of or unable to address it. So with this in mind, I suggest that Reversed Tarot cards do not have a "Use" mechanism. They should trigger automatically based on some sort of event, which consumes the card. They are otherwise normal consumables. When appearing in a Tarot pack, they can be taken, but only if you have room.
Reversed Tarot Cards appear at 5% (or so) the rate of Upright Tarot. Upright Fools copy reversed Tarots as their upright version. If a Reversed Tarot is triggered it is consumed, even if it does nothing. Reversed Tarot Cards block other Reversed Tarot Cards from spawning, additionally upright (e.g.) Fool blocks a reversed Fool and vice versa (and so on), unless Showman is active.
