Monsters you control with 4000 or more original ATK cannot be destroyed by card effects, also your opponent cannot target them with card effects. You can only use each of the following effects of "Endless Darkness" once per turn. During your Main Phase: You can add 1 card that mentions "Endless Darkness" from your Deck to your hand, except "Endless Darkness", then banish 1 card from your hand. If this card in its owner's possession is destroyed by an opponent's card: You can add 1 Level 10 monster with 0 or 4000 ATK from your Deck to your hand.
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