Figure 3: An example of TBW: Here are four red units and four blue units belonging to two players, respectively, on a square board. The units are divided into sword men and archers. The number written in the bottom right of each unit is the unit index. White tilts mean their terrain can be entered. However, ochre ones marked by “” illustrate hilly areas no unit can enter. The dark green tilts marked by letter “” illustrate lakes or rivers, which also cannot be entered, but archers can remotely attack the other side of the tilts.