Overview
Ayu (full name: "Attach Your Units") is a game invented by Luis Bolaños Mures in 2011.

Terminology
Adjacent: always means orthogonally adjacent.
Singleton: a piece with no adjacencies to like-colored pieces.
Group: is a set of like-colored, adjacent pieces.
Unit: singleton or group.

Rules
On each turn, players must complete one of the following actions:
Move a friendly singleton to an adjacent empty point.
Take a piece from a friendly group and place it on a different empty point adjacent to the same group. All stones that were joined in a single group before the move must still be joined after the move.

Every move must reduce the distance between the moved unit and the closest friendly unit. The distance between two units is the shortest path of adjacent empty points between them.

Winning
If a player can't make a move on his turn, he wins.

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