Slitherlink is a logic puzzle where the goal is to draw a loop so each number has that many edges of the loop adjacent to it. Use with [grid-deduction] and [logical-deduction].

Slitherlink is a combinatorial logic puzzle usually played on a square grid.

The rules are simple. Some of the squares contain a number. The objective is to mark the edges on the grid in order to form a single closed circuit with no intersections.

The number of edges of every square that contains a number must match with that number.

Variants exist with other grid shapes, for example see Loopy.