Lifeforce Harmonizer

(1) When your opponent activates a card's effect that inflicts damage, you can discard this card to negate its activation and destroy it.

• The (1) Quick Effect can be activated during either player’s turn.
• This effect can only respond to the activation of a card that is confirmed to inflict damage at resolution.
• You can use "Lifeforce Harmonizer" on your opponent’s card that inflicts damage to themselves, such as "Zombie Mammoth" if there is a situation where it will inflict damage to the opponent.
• This effect can be activated if Caius the Shadow Monarch targets a face-up DARK monster.
• This effect cannot respond to a card / effect that does not / might not inflict damage at resolution.
• It cannot be used against the activation of "Wave-Motion Cannon" or the activation of the effect of "Wave-Motion Cannon" [REF].
• It cannot be used against "Thestalos the Firestorm Monarch" since you don’t know if damage will be inflicted.
• If you control "Des Wombat" and it is preventing you from taking damage, you cannot activate "Lifeforce Harmonizer".