Monodoku's Queens-style puzzle guide

One opening in a row

Scan across a row without an animal. If all but one square are ruled out, the remaining square must hold its animal.

Try the example

The basics / 03

Work through the board

A REAL MONODOKU POSITION4 × 4

Outlines show the reason. Rings show the next move.
Small numbers identify matching colors.

Step 1 of 3

Row 3 has only one square left that can take a piece.

When to use it

Scan a row without an animal from left to right. If every square except one is marked with an X, the row's animal belongs in that opening. The opening's color may still have several available squares elsewhere.

What to watch for

A color does not need to have a single opening for this rule to work. It is the row that forces the placement. First check that your Xs follow from the rules or a proven deduction.

Read the full explanation

Row 3 has only one square left that can take a piece.
Place an animal in the ringed square.
The monkey belongs in row 3, column 4.

Examples use the game's own hint engine. A test placement is temporary; only the proven move is applied.

The same reasoning applies to other Queens-style games, including Meowdoku, with one animal or queen per row, column and color, and no touching, even diagonally.

You'll learn as you play

No need to memorize it all.

Begin with the basics. Monodoku introduces new techniques with a visual lesson when you need them. Hints explain the reasoning, one step at a time.

Try your first puzzle

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