Domino Shade

The grid is divided into outlined regions. Your task is to shade exactly two cells inside each region, and every shaded cell must touch precisely one other shaded cell edge-to-edge, so the shading always comes in two-cell dominoes. Mark cells you have ruled out to keep your deductions straight. Solve the whole grid and the puzzle is complete.

• Shade exactly two cells per region, no more, no fewer.
• Each shaded cell must be orthogonally adjacent to exactly one other shaded cell, forming a domino pair.
• A region tints red if it holds more than two shaded cells; a shaded cell glows red unless it pairs cleanly.
• Use the cross mark to flag cells you know stay empty.
• The board is solved when every region holds a valid domino and no cell breaks the rules.

• Sizes: 6x6 (easy), 8x8 (medium), and 9x9 (hard).
• Daily: one shared puzzle per size each day. Practice: unlimited fresh boards.

• Desktop: click a cell to cycle empty, shaded, cross mark (known empty), then empty again.
• Phone & tablet: tap a cell to cycle through the same three states.

• A single-cell region tip is impossible, so dominoes must straddle region shapes carefully, look at where two cells of a region can legally pair.
• When a region offers only one place for a domino, lock it in and mark the rest empty.
• A shaded cell can never have two shaded neighbours; use that to rule out cells next to a finished pair.
• Cross off ruled-out cells aggressively so the remaining options stand out.

The rules here belong to an established Nikoli puzzle type published as Norinori: shade exactly two cells in every outlined region, and every shaded cell must touch precisely one other shaded cell edge-to-edge.

Because the shading always resolves into two-cell dominoes, and because a domino may straddle a region border, the two constraints are constantly in tension.

That tension is the whole puzzle. A region's pair is easy to place in isolation and almost never placeable in isolation — the partner cell may belong to a neighbour that has already spent its allowance — so the solve propagates outward rather than region by region.

Domino Shade is a free browser version of Norinori, the classic region-shading pencil puzzle: shade exactly two cells in every region, each touching precisely one other shaded cell. Three sizes, daily boards, and endless practice, no download or sign-up needed.

A free, original browser game on PlayPendium. No download, no install.