On the same track as "fifteen puzzle", the game's aim is to enclose all the sheep on the screen inside the fence as quickly as possible with the least moves possible.
The player can move one square at a time between those next to the empty one. Only grass, sheep, fence and dog boxes may move.
The sheep must be gathered in square boxes.
The sheep will be considered gathered only if boxed in the "fence" both horizontally or vertically (diagonal placing is not valid). If necessary, the farm box may be considered as a fence.
A sheep can come close to a wolf only if, once moved, it places itself next to a sheepdog.Then sheepdog can be moved elsewhere. If it's not possible to make a move, the game will be over.