= Partizan game
{title2=$G=\{G^L\mid G^R\}$}
= Partisan game
{synonym}
A <partizan game> gives the two players, traditionally Left and Right, potentially different legal moves from the same position. Its recursive notation is $G=\{G^L\mid G^R\}$, listing Left's and Right's options. An <impartial game> is the special case where those option sets agree at every reachable position.
For example $1=\{0\mid\}$ lets Left move to zero while Right has no move. The game $-1=\{\mid0\}$ reverses the roles, and their <disjunctive sum> is zero in game value: responding in the other component leaves the previous player winning. Such comparisons concern behavior in sums, rather than simply counting moves available to one player.
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