鉄のカーテン~冷戦・暗号解読~

Encrypted messages arrive from behind the Iron Curtain every day.

"The Iron Curtain" is a full-fledged cryptography puzzle game where you play as a Cold War-era codebreaker, deciphering intercepted messages. You are a codebreaker at the Central Cryptographic Bureau. Under the orders of your superior, Frost, you will decipher the codes intercepted from the West one by one.

[6 types of ciphers, from basic to advanced]
* Caesar cipher (Level 1): Shifting letters by a certain number—the first step in cryptography
* Numerical substitution cipher (Level 2): ​​Replacing A with 1, B with 2
* Morse code (Level 2): ​​Reading combinations of dots and dashes
* Substitution cipher (Level 3): Replacing letters one-to-one with other letters
* Transposition cipher (Level 3): Rearranging the order of letters
* Vigenère cipher (Level 4): A challenging cipher where the shift amount changes depending on the key word
Each cipher has its own dedicated input panel (dial, correspondence table, letter assignment, etc.). Even without knowing the mechanisms, you will naturally learn how to solve them while playing. [6 Chapters, 120 Missions for In-Depth Play]
20 questions per chapter, for a total of 120 questions. The difficulty gradually increases with each chapter. If you get stuck, you can use "Reveal a Single Letter" or "Key Hint" to move forward.

[Promote Your Rank as a Spy]
Complete missions to advance through 7 ranks, from trainee spy to the highest rank of Central Director. Your rank is easily visible on your shoulder insignia.

[More Than Just Solving, Learn]
The Japanese meaning of decoded telegrams (KGB, SPUTNIK, etc.) is displayed. While experiencing the atmosphere of the Cold War, you will naturally acquire knowledge of cryptography.

[Recommended for:]
・Those who like puzzles, deduction, and brain training
・Those who like cryptography, spy stories, and the world of the Cold War
・Those who want to play brain-stimulating puzzles in their spare time

All free. Playable offline. Now, comrade, decode the telegrams!