If you've played any hex-based wargame, BOFA will appear quite familiar. The board is hex based, each counter represents a toop of warriors or a single leader. Each counter is rated for movement, combat ability and archery ability. The game is played in turns, each of which has 4 or 6 phases.
Players alternate each phase either moving, firing or fighting.
The chit that you draw is the action that your forces perform this phase. This keeps you guessing as to what you will actually be able to do with your forces on any particular phase. A certain amount of hard decision making goes into which chit you choose. The mechanics of the game are fairly stright forward. On a move phase each counter can move up to its maximum as modified by terrain.