⚪ Masyu
🧩 Logic · 4 playsMasyu
Thread a single loop through every pearl, turning where the pearls demand.
About Masyu
A grid holds white and black pearls, and a single closed loop must pass through all of them. The pearls speak entirely in geometry: the loop travels straight through a white pearl but must turn on at least one of the neighbouring cells, and it turns sharply on a black pearl while running straight through both cells on either side. From two kinds of mark and no numbers at all, remarkably intricate deductions follow — a black pearl near an edge has its directions forced at once, and chains of white pearls along a wall settle whole sections of the loop. The puzzle is solved when one unbroken ring satisfies every pearl.
How to Play
Draw loop segments between cell centres; the loop must pass through every pearl on the grid. The loop runs straight through a white pearl, but must turn immediately before or after it. The loop turns on a black pearl, and must run straight for a cell on both sides of the turn.
💡 Tips & Strategy
Work the edges first, because pearls near a wall are nearly solved already. A black pearl must turn, then run straight for a cell each side of the turn — so a black pearl on the border has its directions forced into the board, and one in a corner is impossible. A white pearl on the border runs straight along the wall, and if it sits one cell from a corner, the required turn beside it is forced too.
Read chains of white pearls as a unit. The loop passes straight through each one but must turn adjacent to it, so three or more whites in a row on a line cannot all be crossed lengthways — the loop must cross them sideways, one by one. Two whites side by side along a wall force turns at both outer ends. These little theorems clear the borders quickly.
For black pearls in the open, enumerate: only four L-shaped passages exist, and every line segment already drawn or forbidden nearby eliminates some of them. Two black pearls adjacent to each other must turn away from one another, since both need two straight cells and there is no room to share.
Finish with the loop laws that masyu shares with every loop puzzle: each cell's dot carries zero or two line ends, dead ends are illegal, and no small ring may close while pearls remain unvisited. When two drawn ends approach, join them only if that completes the puzzle; otherwise the join is forbidden and the deduction from forbidding it is usually the next move.