MASTERMIND Rev. 1.0.16

Number of Colors/Characters (4 - 10)

Allow Duplicates?

Game Mode

Calculated Difficulty Index: 1/10

How to Play Mastermind

The overall goal of the game is to logically deduce a hidden secret code of 4 colored pegs within 10 turns.

The Codemaker (the computer, or your opponent in alternate mode) generates a secret code using the available colors.
Depending on your starting configuration, the code may or may not contain duplicate colors.

To make a move, select colors from the color picker to fill the current row on the board.
You can click a previously placed peg in the active row to remove it before submitting, or use the Clear Last / Clear Row buttons.
Once 4 colors are placed, click the Submit Guess button.

The object of move is to interpret the feedback provided by the Codemaker. After submitting, you receive up to 4 small scoring pegs:

● Black Peg (Exact Match): One of your guessed colors is exactly the right color AND in the correct position.
● White Peg (Partial Match): One of your guessed colors is in the secret code, but it is currently in the wrong position.

No Positional Clues: The placement of the scoring pegs on the board is randomized. A scoring peg's position does NOT correspond to the position of the guessed peg it represents.
One-to-One Matching: Each peg in the secret code can only reward one scoring peg per guess.
Winning/Losing: You win immediately if you receive 4 Black pegs. You lose if you exhaust all 10 rows.

What it is: The 🔮 Oracle button appears on your guessing turns. It is an optional advisor: it never plays for you, and the computer player does not use it.
How it works: It works out every code that still fits all the black and white pegs you have received so far. Then it tries every possible guess against every one of those codes and counts exactly what each answer would leave behind. There is no guessing or random sampling; it is plain counting.
The bars: Each bar shows the share of the remaining codes a guess rules out on average. A tag says whether that guess could win now (it is one of the codes that still fit) or can't be the code. Guesses that can't be the code are sometimes the smartest choice, because they narrow things down faster.
The ranking: When only a few codes are left, the Oracle counts the average number of guesses you would need to win from here, following every possible answer and every best follow-up guess, and ranks by the fewest. Before that it ranks by the most codes ruled out, and upgrades to the exact averages once they finish (up to 15 seconds).
Your guess: If you have already filled in your row, the Oracle rates your guess too, so you can compare it with the best.
First turn: Every guess with the same color pattern (for example, two pairs) scores the same at the start, so the Oracle shows one example of each pattern.