Slitherlink Strategy Guide

Key Strategies

1. 01

   Solve 3s and 0s first

   A 3-clue cell has three of its four sides in the loop. A 0-clue cell has no sides in the loop. Both heavily constrain their corners and force neighboring edges.

2. 02

   Use corner rules for 3-clue cells

   Adjacent 3-clue cells share an edge that must be in the loop. When two 3s share a side, the shared edge is definitely part of the loop and the opposite sides are too.

3. 03

   No dead ends

   Every vertex (dot) in the loop must have exactly 0 or 2 edges. If you draw an edge that would give a dot 3 connections, it's wrong. Use this check constantly.

4. 04

   Diagonal 3–3 pairs lock in edges

   When two 3-clue cells are diagonally adjacent, the edges on the far sides (away from the shared corner) are always in the loop. Mark them immediately.

5. 05

   Track loop continuity

   The loop must be a single closed path. If you see a segment that can only extend in one direction (it would close a small loop before visiting all edges), it's wrong.