Tap and drag through every cell
Tap and drag through every cell
Draw one continuous path that visits every cell exactly once.
The path starts at the marked cell (yellow dot). Drag through adjacent cells (up/down/left/right) to extend it. Drag back over the previous cell to undo a step. Dark cells are walls — you can't enter them.
Tap a far cell anytime to restart from the start cell.
Visit every non-wall cell to clear the board. Each puzzle is randomly generated and always solvable; the next level is a slightly bigger grid.
Goal: clear as many boards as you can.
This is a Hamiltonian path puzzle, and the killer mistake is stranding a cell you can never get back to. Hug the walls and corners first — a corner cell touches only two neighbours, so it must be either your start, your end, or a straight pass-through, which heavily constrains how your line can enter and leave it.
As you draw, keep glancing at the cells you have not visited and ask whether your current move will cut any of them off from the rest. Never paint yourself into a pocket that leaves an isolated empty cell behind, because once stranded it can never be reached. When the path forks, prefer the route that keeps the remaining empty region as one connected blob rather than splitting it in two — a divided board is almost always a dead board.