A03: Crypto Treasure Hunt

HARD LEVEL

Your Mission

This puzzle uses three layers of encryption. You must decrypt them in order:

  1. Layer 1: Caesar Cipher with unknown shift (you must determine the shift)
  2. Layer 2: Keyword-based substitution cipher
  3. Layer 3: Grid-based transposition cipher
⚠️ Challenge Mode: No cipher keys are provided. You must deduce the decryption methods using cryptanalysis techniques and the clues provided.

Encrypted Message (Layer 1: Unknown Caesar Shift)

WKH ILUVW FOXH LV KLGGHQ
ZKHUH BRX VWXGB FUBSWRJUDSKB
ORRN IRU [NHBZRUG EHORZ]
Cryptanalysis Clue: The most common three-letter word in English is "THE". Look for a three-letter pattern that appears frequently in the ciphertext.

Decryption Workspace: Layer 1

Caesar Cipher Analysis

Step 1: Identify the most common three-letter word pattern in the ciphertext.

Pattern found: _____ (this likely equals "THE")

Step 2: Determine the shift value.

If first letter of pattern → T, then shift = _____

Step 3: Apply the shift to decrypt the entire message.

Remember: If A shifted by 3 becomes D, then D shifted back by 3 becomes A.

W (shift back by ___) → ___
K (shift back by ___) → ___
H (shift back by ___) → ___

Partially Decrypted Message:

Layer 2: Keyword Cipher

After decrypting Layer 1, you should have found a keyword mentioned in brackets. Use this keyword to decrypt the following message:

OZMZK ZFK HFFT
GZGUK "RFQAGZUU"
Keyword Cipher Explanation: In a keyword cipher, the keyword is written first (removing duplicates), followed by the remaining alphabet letters in order. This becomes your substitution key.

Example: If keyword is "CRYPTO":
Normal: 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
Cipher: C R Y P T O A B D E F G H I J K L M N Q S U V W X Z

Decryption Workspace: Layer 2

Build Your Keyword Substitution Key

Keyword from Layer 1: _______________________

Step 1: Write keyword (removing duplicate letters):

Step 2: Add remaining alphabet letters:

Step 3: Decrypt the message using your key:

Layer 3: Grid Transposition

The final piece of information is scrambled in this 5×5 grid. Read the location by following this pattern:

Reading Order: Column 1 (top to bottom), Column 3, Column 5, Column 2, Column 4

B
N
E
R
H
E
E
A
T
T
H
A
R
H
E
I
T
T
E
D
N
R
H
O
R

Decryption Workspace: Layer 3

Grid Transposition Decryption

Step 1: Read Column 1 (top to bottom):

B, E, H, I, N → ________________

Step 2: Read Column 3:

E, A, R, T, H → ________________

Step 3: Continue pattern (Column 5, Column 2, Column 4):

________________, ________________, ________________

Final Message from Grid:

Complete Solution

Final Location (All Layers Combined)

Combine information from all three layers to determine the exact location:

💡 Strategic Hints:
  • Layer 1: Try shifts 1-5 first (most common)
  • Layer 2: Make sure to remove duplicate letters from your keyword
  • Layer 3: Write out the columns in order before combining

Next Steps

  1. Complete all three decryption layers
  2. Go to the location specified in your combined solution
  3. Retrieve the physical clue
  4. Return to your desk and proceed to signature verification
⏱️ Time Management: Layer 1: 5 min | Layer 2: 5 min | Layer 3: 5 min. Ask for hints if stuck longer than 3 minutes on any layer.

Team Members: ________________________________ | Hard Puzzle | Page 1 of 1

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