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A partizan game played on a graph attached to the ground. Left removes blue edges and Right removes red edges; after a removal, all edges disconnected from the ground disappear. The player with no legal move loses under the normal-play convention.

A game value lying strictly between $-r$ and $r$ for every positive rational number $r$, in the ordering of partizan games. Infinitesimal values can determine a sum whose numerical part is zero, while they cannot overturn a nonzero integer advantage.

A number game is a recursively defined normal-play partizan game whose options are number games and every left option is smaller than every right option. Its value is the simplest surreal number between those options. Finite number games have dyadic rational values.