
Whenever you cast your first instant, sorcery, or Villain spell each turn, exile it, then exile cards from the top of your library until you exile a nonland card. Lady Loki deals damage to each opponent equal to the difference between that spell's mana valuemana valueThe total amount of mana in a card's cost, ignoring colour. A card costing has mana value 4. X counts as 0 except on the stack. and that nonland card's mana valuemana valueThe total amount of mana in a card's cost, ignoring colour. A card costing
has mana value 4. X counts as 0 except on the stack.. You may cast that card without paying its mana cost.
Hover an underlined rule to see what it means.
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.