In custom battles stupid things result from the artificial red border line. The most aggravating is when your ordinarily highly mobile skirmisher cavalry units passively allow themselves to be pinned against the red border and annihilated by, for example, a slow-moving enemy (A.I.) heavy infantry unit. This is grossly unrealistic. In the real world, such a cavalry unit would be easily able to run away intact and return to fight another day. The way to fix this inaccuracy of the game is to create a special sanctuary zone that would run in a narrow strip along all four sides of the custom battlefield. Light skirmisher units ONLY would be allowed to enter this sanctuary zone. Heavy units in pursuit of said light units would have to stop at the red border and allow the light units to escape. The human player who owns the escaping light units could direct them to move back and forth in the sanctuary zone and reenter the battlefield at his discretion. Light units in the sanctuary zone would not be allowed to launch either missile or melee attacks for as long as they are in the sanctuary zone.