Barrier

This game is played on an empty NxN square board (such as a 7x7 board). Each player drops his stone on an empty cell. On 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). 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). Whoever leaves his opponent with no move first wins.