Damage

Damage is classed into two basic forms, "Battle Damage" and "Effect Damage".

Life Point costs for cards are not considered damage, so cards like Wall of Revealing Light, Final Countdown, and Premature Burial cannot have their costs re-directed via Barrel Behind the Door or negated by Des Wombat.

Battle Damage
Battle Damage is the damage to Life Points sustained from a battle involving 2 monsters on the field or from a monster attacking directly. Also, if a card prevents Battle Damage from being done to monsters, they can't be destroyed in battle.

Effect Damage
Effect damage is any damage that is not caused by battle (with the exception of "") or is a reduction. Examples of cards that cause effect damage are "", "", and "".

Costs are not considered Effect Damage, such as with cards like "" and "". Damage from Monster Cards with "Piercing" effects are considered Battle Damage. Key words to look out for on cards that deal Effect Damage are "Inflict" and "Direct Damage". If it says "Pay" it is a cost.

Some cards are capable of lowering a player's life points without technically inflicting Battle/Effect Damage. Prime examples are and. These cards can be particularly troublesome because they are unaffected by cards such as and, as those cards deal specifically with damage.