Basic FAQ: Battling Monsters

Battle is an action which monsters perform during the Battle Phase. Many cards' effects are triggered when monsters battle. A monster battles when it:
-Is attacked by an opponent's monster (regardless of its battle position).

-Attacks an opponent's monster.

-Attacks the opponent player directly.

-When two monsters battle, the following results may occur.

-If both monsters are in Attack Position, the monster with the lower ATK is destroyed and its controller takes Battle Damage equal to the difference in ATK.

-If the two monsters have the same ATK, both monsters are destroyed and neither player takes damage.

-If an Attack Position monster attacks a Defense Position monster, with DEF lower than the attacking monster's ATK, the Defense Position monster is destroyed and neither player takes damage.

-If an Attack Position monster attacks a Defense Position monster with DEF higher than the attacking monster's ATK, neither monster is destroyed and the controller of the Attack Position monster takes damage equal to the difference in the compared ATK and DEF.

-If an Attack Position monster attacks a Defense Position monster with DEF equal to the attacking monster's ATK, neither monster is destroyed and neither player takes damage.
However, note that card effects may interfere in the above results.