Formats strategic games. For a 2x2 game, for example, the
input: \begin{game}{2}{2} &$L$ &$M$\\ $T$ &$2,2$ &$2,0$\\ $B$
&$3,0$ &$0,9$ \end{game} produces output with (a) boxes around
the payoffs, (b) payoff columns of equal width, and (c) payoffs
vertically centered within the boxes. Note that the game
environment will not work in the argument of another command.
