Waterloo Solitaire can be played as either side. You take the role of Napoleon commanding the French army against an opposing Allied autonomous player side, referred to as the Allied BOT side. And you can take the role of Wellington, commanding the Allied army against a French BOT side. Each opposing BOT side has 3 levels that relate to its skill; Challenging, Veteran, and Tough.

One side is played by you (either Allied or French) and uses player cards for the actions for the side being played. The BOT opponent uses the solitaire actions for the other side that are played via die rolls on the BOT player card.

A player can play one action card per game turn from their hand of cards available for the side they are playing. He also has the option of using Combined Arms Tactics with a supporting card action to the one card action played. Your choices can cause Die Roll Modifiers (DRM) that affect attacks with results that cause unit eliminations and tactical events to occur.