Alexander Against Persia
This is an expansion for the Battleground system, although it can be played as a stand-alone game since it contains both opposing armies and the rules, containing the armies of Alexander the Great and the Persian Empire and explores Alexander’s invasion of Persia. Alexander vs. Persia is compatible with all other Battleground armies; each AvP army can be played against any others in the Battleground system.
To simulate Alexander and his generals leading from the front, the Alexander army features the ability to attach general-specific command cards to a unit and then to replay the card on that unit. The large and relatively unwieldy Persian army enables its general to sacrifice command actions at the start of the game in order to receive extra points for army building.
There are official solitaire rules for the Battleground series of games downloadable at the company website.