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Can attack directly if all monsters your opponent controls are in Defense Position. You can only use each of the following effects of "Dark Tyranno" once per turn. During your Main Phase, if a Spell Card or effect was activated this turn: You can Special Summon this card from your hand. If this card is sent to the GY: You can add 1 Level 8 or higher Dinosaur monster from your Deck to your hand, then you can Special Summon it if your opponent controls a monster.