Slitherlink: Line Logic

Slitherlink is a classic puzzle you might know as Fences or Loopy. Draw lines between dots to make a single unique loop. Each number tells you how many sides the loop uses around that number, and the loop can't cross itself or branch.

Every puzzle has exactly one solution, and you can always work out the next step with logic, so you never have to guess.

If you like Sudoku, it's the same kind of puzzle: pure logic, no luck.

Features:

A new daily puzzle, the same for everyone, that builds up to an Expert puzzle on Saturdays

A calendar for catching up on dailies you missed

12,000 puzzles in Endless mode, on 5×5, 7×7 and 10×10 boards

Four difficulty levels, Easy to Expert, based on the techniques a puzzle needs, not just its size

Saved progress and best times

Solving Help:

A tutorial that teaches one technique at a time

Hints that show the next step a little at a time, and a check for mistakes

A different color for each separate piece of line, so you can see what still needs joining

Leftover sides crossed out for you, and finished numbers dimmed (both optional)

Rule breaks shown right away, like a branch or a loop that closes too early

Features

Optional shading for squares inside or outside the loop

Undo and redo, even after clearing the board

A timer you can hide, and a pause screen that hides the board

Light and dark modes, three color themes, five number styles and soft sounds

Mouse or keyboard controls