Reflect Link

Reflect Link is the name of a class of pen-and-paper logic puzzles published by Nikoli, where one is tasked to draw a path subject to a set of conditions which gets reflected by obstacles on the grid and must link up with itself.

Solved 5x5 Reflect Link puzzle

Description

Reflect Link is played on a finite, two-dimensional, rectangular grid of square cells. Among the empty cell and puzzle border (which can be thought of as the ‘full’ cell), there is the ‘+’ (or ‘crossroads’) cell and the four corner triangle cells {‘◤’, ‘◣’, ‘◥’, ‘◢’}, which may contain indicator numbers. Solving the puzzle involves drawing a loop in congruence with the rules.

Rules

A loop is defined as a path through cell's centres, where two path-adjacent cell centres' corresponding cells must share an edge, that joins itself. Said loop may cross itself on ‘+’ cells and every ‘+’ cell must be visited by the loop in a crossing manner. Triangle cells reflect the loop in accordance with their slope and every triangle cell's center must be on the loop. When a triangle cell is adorned with an indicator number, the loop's maximal subpath which has exactly one turn at the triangle cell's centre must contain the indicated number of cell centres.

Note that the path may turn at its own volition without bouncing off of a triangle cell and may not enter a triangle cell via a cell edge which coincides with one of the two shorter legs of the triangle.

References

• Marshall, James (2023-12-07). "Nikoli Puzzle Rules Summaries ; Reflect Link". Retrieved 2025-06-28.
• "List of puzzle types ; Make a Crossing Loop ; Reflect Link". Archived from the original on 2025-06-30. Retrieved 2025-06-30.