Effect
When an opponent's monster declares an attack, while you have no cards in your hand and this card is in your Graveyard: You can Special Summon this card from your Graveyard, then end the Battle Phase. You can only use this effect of "Tasuke Knight" once per Duel.
Regarding the effect: "If this card is in your Graveyard and you have 0 cards in your hand, when an opponent's monster declares an attack: You can activate this effect; Special Summon this card from your Graveyard, and if you do, end the Battle Phase."
This is a Trigger Effect that can be activated in the Graveyard.
When resolving the effect, you perform the "Special Summon this card from your Graveyard" action, and if the Special Summon is successful, you perform the "end the Battle Phase" action. These actions do not occur simultaneously.
Even if the attacking monster is no longer in the opponent's Monster Zone in face-up Attack Position at the time of resolution, the effect is still processed according to the text.
【Regarding "You can only use the effect of 'Tasuke Knight' once per Duel"】
Even if the activation or the effect of "Tasuke Knight" is negated, you cannot activate the effect of "Tasuke Knight" again during that Duel.
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