The objective is to pair up and connect all the matching colors on the grid with single continuous pipe flows. The pipes cannot branch off or cross over each other. Each puzzle has a unique solution and all the cells in the grid should be filled. This is the classic numberlink puzzle game, with a plumber twist where you must link each color (or resource) to keep the pipe flow. FEATURES: - all the puzzles are free - 4 difficulties (easy, medium, hard, evil) - 8 different sizes (from 5x5 to 12x