Leak proof

How to play Leak proof

Every tile on the board holds a piece of pipe: straights, elbows, tees and crosses. Tap or click a piece to turn it a quarter turn, and keep turning until there is an unbroken run from the tank to the drain. On a desktop you can right click to turn a piece back the other way. The tank and the drain never move. When the run looks watertight, press let it flow and the water sets off. Anything you left open sprays out and counts as a leak. Reach the drain to clear the board. Your score is the number of turns you used against par, plus every leak you sprang along the way.

Tips

• Pipes already joined to the tank light up, so build outward from there
• Count the open ends before you press let it flow, each one is a leak
• A tee only stays dry if all three arms lead somewhere
• Spare pipes are scattered around as bait, you do not have to use them

About Leak proof

Rotation puzzles have been a quiet staple of puzzle books for decades. The setup barely changes: a grid of pieces has been shuffled out of alignment, and you put it right one quarter turn at a time. What makes the plumbing version fun is the payoff at the end. You are not just checking your work against an answer key, you are watching water find every gap you missed, and one open elbow is enough to soak the floor. Our boards start at three by three and grow to eight by seven, with spare pipes scattered around as bait and loops where a tee is the only way through. Nothing is timed, so you can stare at a board as long as you like.

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