See board for rules of play and description.
Scenarios (this may only be meaningful for the regulars):
Default: Version 4 (new): Both black and white start with 4 units in the upper left.
Version 3 ("fixed" live version): Black starts with four units, white starts with 5, four units advanced one square.
Version 2: Black starts with four units and White starts with 5 units in the upper left.