Rules of engagement
Fighting must begin no earlier than sunrise and end exactly at sunset.
Multiple warriors may not attack a single warrior.
Two warriors may "duel," or engage in prolonged personal combat, only if they carry the same weapons and they are on the same mount (no mount, a horse, an elephant, or a chariot).
No warrior may kill or injure a warrior who has surrendered.
One who surrenders becomes a prisoner of war and a slave.
No warrior may kill or injure an unarmed warrior.
No warrior may kill or injure an unconscious warrior.
No warrior may kill or injure a person or animal not taking part in the war.
No warrior may kill or injure a warrior whose back is turned away.
No warrior may attack a woman.
No warrior may strike an animal not considered a direct threat.
The rules specific to each weapon must be followed. For example, it is prohibited
to strike below the waist in mace warfare.
Warriors may not engage in any "unfair" warfare whatsoever.
Most of these laws were broken at least once by both sides.