Numberlink

Overview

Numberlink places matching numbered endpoints on a grid and asks you to connect each pair. Paths move horizontally or vertically between neighbouring cell centres. They cannot cross, branch, join a different pair or form a disconnected loop. The pzpr Numberlink rules used here do not require every cell to be covered, which is an important difference from some similarly presented path games. Leaving an unused square is acceptable when all numbered pairs are correctly connected. That freedom cuts both ways: empty cells are legal, but a path that wastes space can still strangle a neighbouring pair. SonoTap supplies one introductory five-by-five puzzle and its practice rotations and reflections. The selection is honestly labelled as different orientations of the same board. Answer checking runs in the local game engine, and the surrounding guide explains the exact rules before you begin drawing.

How to Play

Drag from a numbered endpoint through adjacent squares toward its matching number. Follow orthogonal steps rather than diagonal shortcuts. Dragging across an existing segment can remove or revise that part of the path, and Undo is available when a correction becomes awkward. Touch users draw directly on the board. You do not need to complete a path in one stroke; extending it a few cells at a time while you test an idea is normal play. Connect all pairs without sharing cells or creating branches, then press Check answer for feedback. Restart clears the paths on the current orientation. The practice selector transforms the introductory board and starts another clean attempt.

Tips & Strategy

Inspect pairs near corners first, where the border reduces the possible exits. A short direct path is not always best if it blocks another pair's only corridor. Treat a completed path as a wall when planning the remaining connections, and consider the space on both sides before committing it. Do not fill empty cells merely to imitate a different game's rules: this implementation permits unused squares. If Check answer reports a loose end, trace each path from its number to the matching endpoint rather than checking only whether the colours look connected. Remove small stray segments left behind during corrections. On any grid, solve the most constrained pairs first and let the flexible long routes take whatever room remains.

Forced First Steps

Endpoints with limited freedom dictate their own openings. An endpoint in a corner of the grid has only two exits; if another path already occupies one of them, its first step is forced. The same logic applies mid-board whenever an endpoint has only one unblocked neighbour.

Consider a concrete case. Suppose the pair labelled two has one endpoint in the top-left corner, and a finished path runs along the top edge directly beside it. The endpoint can no longer move right, so its path must begin downward. If the cell below it also has just one onward square, because the left border and the completed path hem it in, the second step is forced as well. Chains like this can draw half a path before you make a real choice. The mirror-image trap is equally important: an endpoint that already touches its matching number along an edge still cannot step straight onto it if that direct link walls off a third pair. Forced-looking moves deserve one glance at the whole board.

Planning the Whole Board

Every finished path is a wall, and walls divide space. Before committing a route, ask whether the cells on each side of it still leave room for the pairs that must cross that region. A corridor only one cell wide can carry exactly one path; if two pairs both need it, one of them must be rerouted before either is drawn.

Pairs whose endpoints sit far apart deserve early attention, because a long route has many chances to conflict and few chances to improvise at the end. Beginners repeat three mistakes: drawing the geometrically shortest path out of habit, assuming every square must be covered when this ruleset allows empty cells, and forgetting a stray stub segment after an Undo, which later reads as an illegal branch. When the board looks almost solved but Check answer disagrees, hunt for that leftover stub first.