Crowns – a daily logic puzzle with coloured regions

Crowns is a daily logic puzzle: a square grid is split into coloured regions, and you must place exactly one crown in every row, every column and every region. Crowns may not touch, not even diagonally.

Every day you get three boards: an easy one (6×6 or 7×7), a medium one (8×8) and a hard one (9×9 or 10×10). Each has exactly one solution, and each can be solved by pure logic, without guessing.

How to play

1. Tap a cell: the first tap adds an X (no crown here), the second a crown, the third clears it.
2. Drag from an empty cell to put X marks on several cells at once.
3. Clashing crowns turn red: they share a row, column or colour, or they touch.
4. When every row, column and colour has its crown and none clash, the board is solved. You can switch between the three levels at any time; the clock runs per level.

Tips

• Start with the smallest regions: a region of two or three cells leaves little room, so its crown is quickly pinned down.
• If all free cells of a colour lie in one row, the rest of that row can be marked with X.
• A placed crown rules out all eight neighbouring cells, plus its whole row, column and colour.

Strategy

• Look for a colour that lies entirely in one row or one column. Its crown must be in that line, so every other cell of the line can be crossed out, even cells of other colours.
• It works the other way round too: if all free cells of a row belong to one colour, that colour's crown is in this row and the colour's other cells are out.
• On bigger boards, think in pairs. If two colours together cover only two rows, those two rows belong to them, and every other colour's cells in those rows are out. The same holds for three colours in three rows.
• When no safe move is left, test a cell in your head: if a crown went here, would every colour still have room? If a crown on a cell would wipe out all cells of some colour, that cell is an X.

A worked example

An invented example on a 6×6 board: the yellow region is just the second and third cells of row four. Wherever the yellow crown goes, it is in row four, so the other four cells of that row are X.

The cells above and below the two yellow cells matter too: whichever yellow cell gets the crown, the second and third cells of rows three and five touch it, so they get an X as well. Two small steps, and six cells are already out.

History of the game

The game belongs to the Star Battle family of puzzles, popularised in the early 2000s on the puzzle-championship circuit, with Dutch puzzle author Hans Eendebak among its best-known setters. The classic version often has two stars per row, column and region; our daily board is the one-star version, with one crown everywhere.

The no-touching rule on a grid recalls the eight queens problem in chess, where eight queens must be placed so that none attacks another. The coloured regions call for a different way of thinking, though: here the shape of an area gives the answer away.

Frequently asked questions

Is there always a solution?

Yes, exactly one. Every board is checked by a solver before it goes live.

Do I ever have to guess?

No. We only publish boards that can be solved step by step with logic. The hard level needs longer chains of reasoning.

Do the X marks count?

No, they are only there to help you. Only the crowns decide the solution.

What if I get stuck?

The Solution button (two taps) shows the answer. The level then ends, but it does not count as solved.