Keep Talking and Nobody Explodes Mod Forest Cipher

On the Chopping of The Forest [Cipher]

Original Manual

Step 1: Chain Bit-Rotation Cipher

For this step, you will need everything on page 1, which we will call the encrypted word, the initial number, and the keyword, respectively. If the keyword is shorter than 6 letters, append a repetition of it to it.

Assign the initial number A and the alphabetic positions of each letter in the encrypted word (A1Y25Z0) B - G respectively. Calculate this expression:

((((((A * 26) + B) * 26 + C) * 26 + D) * 26 + E) * 26 + F) * 26 + G

Convert this result to binary, padding leading 0s until there are 30 binary digits. Now, starting with a value n of 30, carry out the following steps 6 times:

  • Cycle the least significant n bits to the right by m bits. Here, m is the alphabetic position of the next letter in the keyword (A1Z26).
  • Remove the last 5 bits from the number and convert them to a letter (A = 00001 ... Z = 11010).
  • Reduce n by 5.

Example

Encrypted word: XOGXTU; initial value: 2; keyword: DINE
Calculation: (((((2×26 + 24)×26 + 15)×26 + 7)×26 + 24)×26 + 20)×26 + 21 = 909979013
Binary: 909979013 = 110110001111010010110110000101

Cycle 30 bits right by D=4: 010111011000111101001011011000 → 24 → X
Cycle 25 bits right by I=9: 0100101100101110110001111 → 15 → O
Cycle 20 bits right by N=14: 11001011101100010010 → 18 → R
Cycle 15 bits right by E=5: 110001100101110 → 14 → N
Cycle 10 bits right by D=4: 1001110001 → 17 → Q
Cycle 5 bits right by I=9: 00111 → 7 → G

New Encrypted Word: XORNQG

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Keep Talking and Nobody Explodes Mod Forest Cipher

Step 2: Semaphore Rotation Cipher

Five points for creativity. It goes to five by the way.

For this step, you need the encrypted word obtained from step 1 and the keyword from the top screen on page 2.

Take the alphabetic positions of each letter in the keyword and modulo each value by 8. Then apply this for each letter in the encrypted word:

  1. Find the Xth encrypted letter on the table provided.
  2. On the same row, count that many tiles to the left, Y times, where Y is the Xth value obtained before, wrapping around to the other side of the row if necessary. This is the Xth decrypted letter.
    • NOTE: If you get any of the dashed letters, YOU MAY HAVE DONE THE PREVIOUS STEP(S) INCORRECTLY.
A
H
O
T
-
W
Z
G
B
I
P
U
J
X
F
N
C
K
Q
Y
V
E
M
S
D
L
R
-

Example

Encrypted word: XORNQG; keyword: LOUDER

XORNQG
L (12): 4O (15): 7U (21): 5D (4): 4E (5): 5R (18): 2
I T L U E W
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Keep Talking and Nobody Explodes Mod Forest Cipher

Step 3: Monoalphabetic Rubik’s Cube Cipher

This step uses the encrypted word from step 2 and the keywords on the middle (keyword A) and bottom (keyword B) screens on page 2.

First, create an alphabet key from keyword A. Append the full alphabet to it, then remove all duplicate letters (retain first occurrences).

Create two 3×3×3 cubes. The first, cube A, should be filled with letters A–Z as shown in the diagrams below (note that the center cubelet is omitted). The second, cube B, must be filled with the alphabet key in the order in which the below diagrams have the letters KENVMPABCDFGHIJLOQRSTUWXYZ. (Mnemonic: fill the face centers first in the below order, then the rest of the front, middle and back layers in reading order as seen from the front.)

For each letter of keyword B, perform one of the below rotations on cube B (meaning: cycle the eight highlighted letters in the indicated direction, which is always clockwise when looking toward the relevant face of the cube) a number of times as given by the table underneath.

U X R U X R U X R U M O J M O J M O J M O M J M D G D G A D G A D A S V Y S V Y V Y V S V Y S V K P K P K P K P K P K P E E H B E H B E H B E H E B T W Z W Z T W Z T W L N Q N N Q L N Q L N Q L N F I F I C F I C F C R R U X R U X X J J O O A D G A D G A G S S Y Y H B B H T W Z T W Z T Z L Q L Q F I C C F I C I Up Front Right Back Left Down ABCDY EFGHZ IJKL MNOP QRST UVWX
Letter from keyword BAEIMQUYBFJNRVZCGKOSWDHLPTX
Number of cycles1357

Finally, find each letter of the encrypted word in cube B and replace it with the letter in the same position in cube A. When completed, you obtain the deciphered word.

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Keep Talking and Nobody Explodes Mod Forest Cipher

Example

Encrypted word: ITLUEW
Keyword A: SINKING → key: SINKGABCDEFHJLMOPQRTUVWXYZ
Keyword B: VINE → rotations: 3×D, 1×R, 3×B, 1×F

B C D E I F M S O G N A R T U V K W B C E I Y X M S G N Z A R T V K Q L B C F E I P Y X H M S D G N Z A J K I M S D G N Z A J U W L O K Q T R V B C D E I F H J L M S O G N P A Q R T U V K W X Y Z Initial 3 × Down 1 × Right 3 × Back 1 × Front Final Y X P Z H Q L J F P H D J O U W U W L O Q T R V E B C Y F X H P E B C Y I F X H P M S D G N Z A J U W L O K Q T R V
E B C Y I F X H P M S D G N Z A J U W L O K Q T R V A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Cube A Cube B

I → E
T → X
L → T
U → R
E → A
W → S

Deciphered Word: EXTRAS

Step 3A: Altered Monoalphabetic Rubik’s Cube Cipher

Due to how the cipher is set up, this trick can be abused. Examine the tables on the next page and line up your alphabet key with the letters on this table. Rearrange these based on the transformations used on this module. The first 6 letters of that key are NEVER altered. Compare this with KENVMPABCDFGHIJLOQRSTUWXYZ to decrypt.

If ONLY using the focused letters, overlay KENVMPABCDFGHIJLOQRSTUWXYZ directly above the alphabet key. Extract the letters from the alphabet key that match the focused letters above. Take the last X letters of this and place them at the front. Then insert the transformed letters back in the same position as the letter that was extracted from. Do this for each letter in keyword B.

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Keep Talking and Nobody Explodes Mod Forest Cipher
KENVMPABCDFGH IJLOQRSTUWXYZ
1x Front
KENVMPDABGCHI FJLOQRSTUWXYZ
Focused Letters
ABCFIHGD
1x Back
KENVMPABCDFGH IJLOQSTWRZUXY
Focused Letters
TSRUXYZW
1x Left
KENVMPJBCAFDH IRLGQRSTXWOYZ
Focused Letters
RJADGOXU
1x Right
KENVMPABFDIGH QJCOZRSLUTXYW
Focused Letters
CLTWZQIF
1x Up
KENVMPBCLDFGH IATOQJRSUWXYZ
Focused Letters
AJRSTLCB
1x Down
KENVMPABCDFOG HJLXIRSTUWYZQ
Focused Letters
GHIQZYXO
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