"Larfin's Four Sevens" I believe this to be a breakthrough method of doing the Fitch Cheney trick where the spectator gets to choose the target card!

Even though the spectator does not choose the four signal cards they do choose the target card which I think meets the spirit of Rusduck's challenge.

This method also relies on the fact that the seven of spades and seven of clubs are one way cards on the face (the middle suit pip points up or down depending on the orientation of the card).

Effect: The magician removes the 4 sevens from a normal deck of playing cards and throws them face up to one side and says "these are the General's detectives and will tell headquarters who the traitor among them is". The magician has his assistant leave the room or turn their back. The magician then says to a spectator "I want you to pick any card from the rest of the deck to be the traitor and show it to us and then turn it face down on the table and cover it with your hand so my assistant never sees the card, also hide the rest of the deck somewhere so no information can be gained from it".

The magician then arranges the four sevens in a special sequence and the magician then tells the spectator "give these four sevens to my assistant and these 4 cards will tell my assistant the traitor's name". The assistant returns and looks at the four sevens, thinks a little bit, then names the traitor (the target card name)! Note that the assistant could stay in another room and write the name of the traitor (the target card) on a piece of paper for the spectator to bring back to read to the audience.

Okay here's the 4 sevens method:
a. the seven of diamonds position designates the suit (Stewart James method) but use SHCD sequence. For use of the other three sevens see immediately below:
b. the seven of spades always has a value of one (1 point on the pip)
c. the seven of hearts always has a value of two (2 lobes)
d. The 7 of clubs always has a value of 3 (three leaf clover)
e. these three sevens are arranged around the seven of diamonds to form a number according to the Fitch Cheney 1-6 value.
f. If the middle pips of the seven of spades and seven clubs are pointed the same way then add seven to the 1-6 value (If they are pointed in opposite directions to each other then stay with the 1-6 value).

Examples:
Note that for any target cards lower than seven arrange the 7C and 7S middle pip to point in opposite directions.
Note that for any target cards higher than seven arrange the 7C and 7S middle pip to point in the same direction (and mentally add 7 to the 1-6 value).

To encode the two of spades:
7D 7S 7C 7H

To encode the two of clubs:
7S 7C 7D 7H

To encode the five of hearts:
7C 7D 7S 7C

To encode the queen of clubs:
7S 7C 7D 7H

To encode the king of clubs:
7C 7H 7D 7S

To encode the king of diamonds:
7C 7H 7S 7D

To encode the six of diamonds:
7C 7H 7S 7D

To encode the 10 of spades:
7D 7H 7S 7C

To encode the ace of spades:
7D 7S 7H 7C

In addition to the spectators there are two people openly involved (the magician and an assistant, referred to here as the sender and receiver). Initially when the four sevens are displayed the sender throws them face up hap hazardly on the table so (after the receiver leaves the room or turns away a spectator selects a target from the other 48 cards) this will allow the sender to straighten either the seven of spades or the seven of clubs appropriately without calling attention to that fact.

Note that the sender can arrange the seven of spades and seven clubs to both point up or both point down to signal cards eight through the king, it doesn't matter which direction as long as they're both pointing the same direction.

When determining the 1-6 value ignore the 7D and focus on the other three sevens.

7S 7H 7C = LMH = 1 Ace or 8
7S 7C 7H = LHM = 2 or 9

7H 7S 7C = MLH = 3 or 10
7H 7C 7S = MHL = 4 or 11 Jack

7C 7S 7H = HLM = 5 or 12 Queen
7C 7H 7S = HML = 6 or 13 King

Let's go through an example of the receiver (the assistant) decoding the following:
7C 7D 7S 7H
First the assistant looks immediately for the seven of diamonds and sees that it's in the second position of the agreed upon SHCD theoretical positions therefore knows instantly that the target card is a heart.

Next the assistant looks at the very first non 7D seven and sees that it is the 7C which is the highest of the three which tells him instantly this represents the number five or six.

Then the assistant looks at the other two sevens and if the lower one comes first then the number we're looking for is five, if the higher seven then number is six. Since in our example the seven of spades is lower than the seven of hearts the assistant knows the number is five.

So at this point this assistant knows that the target card is either the five of hearts or adding seven is the 12 of hearts ie the Queen of hearts.

The assistant looks at the seven of spades and the seven of clubs and sees that they are pointing in opposite directions therefore the target card (the traitor) is and the lower six ie is the five of hearts and announces "the five of hearts is the traitor"!

This Four Sevens method simplifies several things.
1. ensures that there will be three one-way cards (the seven of clubs, seven of hearts, seven of spades are all one way on their face).
2. simplifies the problem of the kings that most systems have (by removing the sevens this means the eight through the king is reachable with a value of 6).
3. Don't have to use second method (Derek Chung's secondary binary method, which I think is really cool but this 4 sevens's method does not need it).
4. All four signal cards (the four sevens) are face up (unlike some other methods that require face down signal cards).
5. does not use the pigeonhole two cards of same suit as does Fitch Cheney.
6. All the rest of the cards are potentials for the spectator to choose as the target card.

Be sure to look at the clever Derrick Chung method which has some similarities especially the Stuart James part for the target suit and then the placement of the other three cards but ignore the binary scheme and ignore the face down scheme as you don't need it for my four sevens method. Derrick Chung's Rusduck criteria:
https://youtu.be/t-0mBqmENgo

Your comments pro and con are welcome.

Note that the magician and assistant could agree to switch from the seven of diamonds to use the seven of hearts after doing the effect two times (use the seven of diamonds the first two times you do the trick then use the seven hearts the third and fourth times you do the trick).

I plan to make a YouTube video on this but it may be a while.

Instead of 4 sevens as the signal cards you could use 4 aces, or 4 threes, or 4 fives, or 4 sixes, or 4 nines but you must remove (secretly ahead of time or openly) the 4 sevens from the deck because the spectator must not choose a seven as the target card.

Note that by using the orientation of two cards (the seven of spades and the seven of clubs) this prevents any chance of the spectator twisting the whole 4 card packet in an incorrect orientation (they can't mess it up).

For you bridge players out there you can always change from SHCD to CDHS for the suit position of the 7S.

And also change to use the suit relative values as:
clubs equals 1
diamonds equals 2
hearts equal 3

You could also use the 4 eights because they are "one way" (of course the sevens would have to be removed).

I just thought of a way to use the 4 aces instead of the four sevens and be able to signal if the target card was a seven. Here is how: use the orientation of the ace of hearts center pip to signal that the target card is a 7 simply by making the ace of hearts center pip be oriented the opposite way of the ace of spades center pip (of course this means the ace of hearts must be oriented normal to the ace of spades center pip for the normal signaling process). But this could be risky and just another thing that could go wrong therefore if using the 4 aces instead of the 4 sevens then the safer way is just to remove the 4 sevens from the deck and not use the Ace of hearts center pip to mean anything.

Back to my Four Sevens method:
What if we wanted the spectator to whisper or write down the traitor card name? Then it might be possible that they could name one of the sevens as the traitor. My current scheme does not handle this situation however the heart pip orientation (vs the spade pip orientation) could be used to solve this. However we avoid this problem by having the spectator pick a card from the 48 cards which of course do not have any sevens.

His name is Stewart James not Stuart James.

I like your method.

Here’s a possible way to handle the cases when a Seven has been selected.

Table the 4-card packet face down, either vertically or horizontally, either in a tight bunch or slightly spread. Those cover the 4 possible suits.

It would actually be very baffling to the audience.

That'll work, neat idea thanks Claudio you always have clever ideas!
My preference is for me to arrange the 4 cards in the proper sequence and once the target card is selected I don't say a thing that my assistant can hear and I have a spectator take the packet to my assistant whose back is turned the whole time and then my assistant divines the target card. The reason I like to do it this way is because if my assistant faces the table and or me before divining the card then there are a hundred extraneous signals that could be given such as my hand to my chin, my right foot forward, a spoken keyword, a pen or pencil on the table, the cards being close to the card box on the table, etc, etc. Knowledgeable people in the audience may know this and be unimpressed with this trick therefore if my assistant is somewhat isolated and it appears that the only possible knowledge they have comes from the four card packet they are holding then I think that heightens the effect of this trick?

OK, I get your presentation and I agree.

So, what about handling the packet face down to your helper to signal it’s a Seven? Your helper will hand over the packet in whichever orientation they received it to your assistant. If you have any doubt, just ask the helper to extend their hand flat and drop the packet on it and instruct them to hand over the packet to your assistant. You can easily motivate this in accordance with your presentation.

In general, I don’t find this kind of demonstration very impressive unless you end with a very strong effect. Here’s a possible routining in which the 3rd and last card reveal looks “miraculous” (forgive the hyperbole )

First, decide beforehand a specific force card with your assistant, say the 3H.

Have the deck shuffled by a helper while your assistant has their back turned. Pick up the deck and in the process of taking out the 4 sevens bring the 3H to the top.

Ask the helper to cut about 1/3 of the deck from the top, turn the packet face up and drop it on top of the deck. The top face-up card is the first card you have to code.

Next, the helper cuts 2/3 of the deck from the top, turns it over and drops it on top of deck. You code this second card.

Finally, for the tour de force of this routine: All face-up cards are discarded and the 1st face down card is removed by your helper who looks at it, but is unseen by you or anyone else. Ask your helper to think intensely about their card and that your assistant will try to read their mind. They do.

I think that the use of the Cut Deeper Force is perfectly motivated in that setting, and unless there are magicians in your audience, this routine should leave your audience very impressed if not amazed.

Just an idea to play with.

I don’t think your method is better, from a presentational point of view, than the Fitch Cheney one in which the spectator selects 5 random cards, but it certainly has merits and I can see it being used along with the original to build a strong routine.

In my post above I described a magic finale to the 3-divination effect. But if you want to fry the brain of people who know the original method (and are not magicians or ignore the Balducci Force), you could end this way: Ask your helper to give you any three face-up cards and then to turn over for everybody to see the 1st face-down card.

Pretend to arrange your 3 cards which are then seemingly used by your participant to decipher the last card. Less powerful but will get the connoisseurs in your audience crazy.

N.B. When I used to perform this effect with the Cheney method, I'd allow the spectator to "select" the target card. I was in fact either using a Magician's Choice or a Pateo Force (which is great in this situation). A Glide would work well too here.

How to turn a seven upside down without the audience knowing that's what you did: magician holds a fan of 4 sevens in his left hand facing himself and with his right hand pulls out say the seven of clubs with his thumb at the top face and his index finger at the top back and wipes the face of that card across the top of the target card saying something like "he's taking a picture of the traitor" or "he's getting his fingerprints". Then with his right hand still holding the seven of clubs he raises his hand vertically so his palm is facing the audience and the card is facing the audience. Next the magician twists his right wrist 180 degrees and is now holding the 7 clubs at the bottom facing himself (right thumb at the bottom face and the right index finger on the bottom back). Use the right middle finger to push up the bottom left of the card a little bit. The card has now been rotated 180 degrees so now just put it back in the fan where it was.

I've changed my mind and I like the four eights better than using four sevens. There are three reasons:

1. On the eights the middle big pip that is one way can easily be viewed in a little fan that the magician holds whereas the center pip on the seven is not as easy for the magician to see (you have to spread the cards much more) and remember you need to easily be able to see both black sevens center pip to know whether to reverse the seven of clubs.

2. The imbalance of the center pip on the sevens can much more easily be noticed by the audience ("where" it is on the card) whereas with the the eights the pip placements are perfectly balanced it's just the pip itself that is turned up or down on the center row and are almost impossible for the audience to notice.

3. If a seven is chosen as the target just signal the value 8 (your assistant will understand that that means the target is a 7).

Note that the four sixes could be used instead of four eights and four sixes have the same benefit as the four eights (and signal a value of 6 if a 7 is chosen as the target).