RULES

How to play Cipher Mosaic

The computer generates a secret code. You only know its length and the set of available values. Your goal is to reconstruct the entire code in as few guesses as possible.

1. Set the difficulty

Choose from 2 to 30 positions and from 2 to 30 available values. Blank is one of those values. Repeated values are allowed.

The leaderboard category is number of colors × number of positions. Example: 6 values and 4 positions give category 24.

2. Build a guess

Click each slot to choose a color or blank. After pressing “Check”, the game returns only two numbers:

• exact — correct color in the correct position,
• misplaced — correct color in the wrong position.

The clue never reveals which slots it refers to.

3. Repeats without double counting

All exact matches are removed from comparison first. The remaining values are then compared, and every element of the secret code can be matched at most once.

Code: red, red, blue, green.
Guess: red, yellow, yellow, yellow.
Result: 1 exact and 0 misplaced. The second red in the code does not add another match because red appears only once in the guess.

4. Blank is a color too

Blank may appear in the code and is scored exactly like any color. It may occur multiple times. In the interface it is marked with Ø.

5. Notes and locks

The global palette is your private notebook. Click a color to cross it out. You can still use it in a guess because the game never assumes your deduction is correct.

Every slot has a small lock inside the color. Locking a slot copies that value into your next guess. The lock is not confirmation from the game.

6. Leaderboard

Players who solve the code in fewer guesses rank higher. If the number of guesses is identical, the shorter completion time wins. The table also shows the actual setup, for example 4×6.