Battle damage (Japanese: 戦（せん）闘（とう）ダメージ Sentō Damēji) is the damage inflicted to a player's Life Points from battle. Battle damage can be inflicted when two monsters battle. * If the attack target is in Attack Position: * If the monsters have different ATK, the controller of the monster with the lower ATK takes battle damage equal to the difference. * If the attack target is in Defense Position: * If the attack target's DEF is greater than the attacker's ATK, the attacking monster's controller takes battle damage equal to the difference. * If the attack target's DEF is lower than the attacker's ATK, the attack target's controller does not take battle damage, unless the attacking monster inflicts piercing damage.