A Charm refers to a blind-play in which someone plays an unrelated card from their Fourth Finesse Position. For example, if a player's hand is completely unclued, their Fourth Finesse Position is slot 4.
Charms fall outside of the Signal Shift framework. Instead, playing from Fourth Finesse Position is required in order to disambiguate the clue from being a Finesse, Ejection, or Discharge.
Just like a Bluff, a Charm can only be performed on the very next player.
Interaction with Double Bluffs Where Cathy Has a One-Away-From-Playable Card
As stated in the level 24 section, Double Bluffs have precedence over 4 Charms. However, there is one small exception.
Double Bluffs do not have precedence in the situation where Bob sees that Cathy has a one-away-from-playable card on her Finesse Position. Here, it is technically possible that Bob will blind-play the exact card that makes Cathy's Finesse Position playable. But since this is so unlikely, we agree that players in this situation should revert to a 4 Charm interpretation.
For example, in a 4-player game:
Red 1 is played on the stacks.
Alice clues blue to Donald, touching a blue 4 as a Play Clue. (Blue 4 is currently three-away-from-playable.)
Bob sees that Cathy has a red 3 on her Finesse Position.
If Bob has exactly a red 2 on his Finesse Position, then he knows that Alice's clue would work as a 4's Double Bluff.
However, since the red 3 on Cathy's Finesse Position is one-away-from-playable, Bob knows that 4 Charms should take precedence.
Bob blind-plays his Fourth Finesse Finesse card. It is a red 2 and successfully plays on the stacks.
The Out-of-Order Finesse always takes precedence over a 4 Charm or a 4's Double Bluff, because of Bob's Truth Principle.
For example, in a 4-player game:
It is the first turn and nothing is played on the stacks.
Donald's hand is as follows, from left to right: red 4, red 1, blue 3, blue 3
Alice clues red to Donald, touching the red 4 on slot 1 and the red 1 on slot 2. This is a Play Clue.
Bob knows that this could be the truth as an Out-of-Order Finesse. If that is the case, he should clue number 4 to Donald, allowing him to play the red 1. Then, Bob can blind-play the red 2 and the red 3 (into the playable red 4).
Bob knows that this could also be a 4 Charm, since the red 4 is three-away-from-playable and Bob does not see any other red cards on Finesse Position.
However, Bob knows that he should always assume the truth over a lie, so he assumes that Alice intends for an Out-of-Order Finesse.
Normally, after an Unknown Trash Discharge, non-focused cards are known to be "good".
However, what if a player performs an Unknown Trash Discharge where all of the non-focused cards are trash? A Discharge would incorrectly signal that the non-focused cards are useful.
Instead, this should signal a Charm on the very next player.
For example, in a 3-player game:
All of the 2's are played on the stacks.
Alice clues red to Cathy, touching a red 1 on slot 1 and a red 2 on slot 2.
Normally, Bob would treat this clue as an Unknown Trash Discharge. However, if he Discharges, then Cathy will discard the red 1 and mark the red 2 as either a red 3, a red 4, or a red 5, which would be a Lie.
Instead, Bob knows that this signals an Unknown Trash Charm, so he blind-plays his Fourth Finesse Position. It is a blue 3 and it successfully plays.
Sometimes, when giving a number 1 Play Clue for 1's, a Bad Touch is unavoidable. But what if a player does this when a color clue would have avoided a Bad Touch?
If all the non-focused 1's are trash, the clue must be calling for something extra - a Charm on the very next player.
After the Charm occurs, the clued player will know that only the focus of the 1's clue is playable.
For example, in a 3-player game:
Green 1 is played on the stacks.
Alice clues number 1 to Cathy, touching a red 1 on slot 5 and a green 1 on slot 2.
Cathy's hand is, from newest to oldest: yellow 2, green 1, blue 3, purple 5, red 1
Bob can see that Alice could have clued red to only touch the red 1 and avoid a Bad Touch.
Bob knows that this signals a blind-play:
A Finesse Position blind-play would look like a Trash Finesse, which would be a Lie.
A Second Finesse Position blind-play would look like a Trash Push Ejection, which would be a Lie.
A Third Finesse Position blind-play would look like a Unknown Trash Discharge, which would be a _Lie.
Thus, Bob knows this must be a Junk Charm and blind-plays his Fourth Finesse Position. It is a blue 1 and it successfully plays.