At each turn, each player must move his stone. The stone moves similar to a chess Knight, but in two steps rather than one. First it moves one (two) cell(s) in one direction, then two (one) cell(s) orthogonally (hence each player has two moves per turn).
Initial position
The First Move
The Second Move
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All positions moved to or jumped over turn into an impenetrable barrier for both players (i.e., they cannot be moved into or jumped over).
