Loop Links: settle the boundaries before closing a small circuit
Use a corner’s forced directions, check reciprocal pipe ends and avoid mistaking several neat little loops for the one route that must visit the whole board.
Worked examples use the Standard board unless a different size is stated. Hard and Expert may change the board dimensions or amount of information to track.
The outer boundary supplies free constraints
Every Loop Links piece has two pipe ends, and neither may leave the board. This makes the corners useful starting points. At the top-left corner, a valid piece must connect east and south: north and west would point outside. A corner piece in that square therefore has only one legal final orientation.
Other edge squares still restrict choices. A straight piece on the top edge must run horizontally, because a vertical straight would leave through the top. An edge corner may have more than one inward orientation. Distinguish a forced rotation from a choice that needs information from the next square.
Read a connection from both sides
Suppose one square sends a pipe end east into its neighbour. The neighbour must send an end west back toward it. An east-pointing line beside a neighbour whose ends point north and south is not a completed connection; the two pieces merely sit next to each other.
After rotating a piece, inspect both of its ends. Repairing its connection to the left can break an earlier connection above. A useful plan follows the route through the square rather than checking only the end that motivated the click. A screen reader can announce each button’s current pipe directions, providing another way to follow the bends on the board.
A closed local circuit can still be wrong
Four corner pieces can form a tidy loop around a two-by-two block. All their ends meet and none are open. On a larger board, that little circuit is nevertheless insufficient because the remaining squares are outside it. Completion requires every piece to belong to the same single route.
Following a route that returns to its starting square early tells you that it has closed off part of the board. If unused squares remain, revisit a choice that joined the local circuit. You cannot repair that isolation merely by making another independent loop elsewhere. Several disconnected circuits fail the same global requirement even when every local connection is reciprocal.
Use rotation history to compare route choices
A normal activation rotates clockwise. Holding Shift while clicking or using Enter or Space rotates counterclockwise, and Undo reverses the last accepted rotation. Restart restores the same scrambled orientations. The displayed count measures the current rotation sequence, not how many pieces remain incorrect or how far the whole board is from its nearest solution.
The generated pieces come from a full-board closed route, so some arrangement of their rotations works. That does not make the preferred route unique or provide a minimum-move answer. Start with boundary constraints, extend reciprocal connections, and keep asking whether an apparent completion has left another region outside the circuit. The target is one continuous visit to every square, not a collection of locally attractive shapes.
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