
EerieEerieAbility word: triggers whenever an enchantment enters under your control and whenever you fully unlock a Room. — Whenever an enchantment you control enters and whenever you fully unlock a Room, surveilsurveilLook at that many cards from the top of your library, then put any number into your graveyard and the rest back on top in any order. 2 if this is the first time this ability has resolved this turn. If it's the second time, each opponent discards a card. If it's the third time, put a creature card from a graveyard onto the battlefield under your control.
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Read from the rules text. A card that enables a keyword makes or is the thing; a card that rewards it gets better when you have it. Two cards interact when one enables what the other rewards.