Pipes,
rotate the water home.

Pipes is a rotation puzzle. The board is filled with pipe segments — straights, elbows, T-junctions, crosses, and terminals — connected to one source. The pieces have been spun around at random, and your job is to rotate them back so the water flows from the source through every pipe to every terminal with no loose ends.

Tap any pipe tile to rotate it 90° clockwise. Tiles flowing with water turn sage-green so you can see your progress. Solve the board by reaching every pipe from the source and leaving no openings pointing into walls.

Long-press a tile (or right-click on desktop) to lock it. Locked tiles get a moss border and can no longer be rotated until you unlock them the same way. Useful for marking tiles you know are correct so you don't accidentally rotate them later.

The clay-red dot in the middle of one tile is the water source. The smaller dots at the end of single-ended pipes are terminals. Every terminal must receive flow; if even one is dark, you're not done yet.

Easy is a 5×5 grid, Medium is 7×7, Hard is 9×9. Each step up adds more tiles and more branching to the underlying tree, so the same "rotate to connect" mechanic gets steeper without changing the rules.

Each puzzle starts from a random spanning tree rooted at the source — a tree that touches every cell in the grid exactly once. Each tile's shape is the union of edges that touch it in the tree, then every tile is randomly rotated. The puzzle is always solvable by construction: rotating each tile back to its original orientation reproduces the tree.

A 4-way cross looks the same in every orientation, so rotating it would be a no-op. The board skips rotation for those tiles silently — they stay fixed throughout the puzzle.

Yes. Single-tap rotates, long-press locks. The grid scales to your screen width up to 480px wide, so phone-sized boards have nice big tap targets without feeling cramped on a tablet.