Draw one loop
Join neighbouring dots with horizontal or vertical edges to form one closed loop. The line cannot branch, cross itself or split into separate loops. Every dot used by the finished loop has exactly two connected edges.
Slitherlink
Getting your game ready…
How to play
Count around a clue
A number inside a cell tells you how many of its four surrounding edges belong to the loop. A zero rules out all four; a three needs three of them. Empty cells give no number requirement, but their edges still belong to the same loop.
Mark what you know
Tap an edge to cycle line, X and empty, or use the Line/X/Clear tools. X rules an edge out. Meeting every local number is not enough: the finished line must be one loop. Undo reverses a change; Restart clears the current puzzle. Six fixed puzzles let you choose another board.
Strategy
Use the corners of a clue
Two chosen edges meeting at a dot leave no room for a third. Carry that restriction into the adjacent cells. A number tells you how many sides it needs; the dots tell you which arrangements can connect without branching.
Do not close too soon
A small loop may satisfy nearby numbers while cutting off an unfinished section elsewhere. Before adding an edge that closes the line, check whether any required edges remain outside it. The final closure must join the whole route.
About the game
Numbers beside a line
This compact puzzle uses five-by-five cells and a six-by-six lattice of dots. Its two scales work together: count one cell’s borders, then check the line across the board. Completed puzzles and your selection are remembered; unfinished marks are not.