On the Subject of the Scytale CM

A machine that knows no bounds when it comes to ciphers.

Determine the amount of rows used in this transposition by converting the letter on screen 1 to a Value via the Value Table. Then take the Value, modulo it by the encrypted word’s length minus 2, plus 2. The resulting value is the number of rows used by this transposition.

If the Submit Button is white, follow the instructions under Encrypt Instructions. Otherwise follow the instructions under Decrypt Instructions.

Encrypt Instructions

  • Write the encrypted word, top to bottom, left to right.
  • Read the letters left to right, top to bottom to get a decrypted word.

Decrypt Instructions

  • Write an X amount of asterisks, top to bottom, left to right. X is equal to the encrypted word’s length.
  • Replace each asterisk with the letters of the encrypted word in reading order.
  • Read the letters top to bottom, left to right to get a decrypted word.

Example 1

Encrypted Word: BNIGEDN
Rows: (22 mod (7 - 2)) + 2 → 4
Using Encrypt Rules


Decrypted Word: BENDING

Example 2

Encrypted Word: FELSI
Rows: (19 mod (5 - 2)) + 2 → 3
Using Decrypt Rules



Decrypted Word: FLIES