Guardian Angel is a common Instant card from Limited Edition Alpha (LEA), collector number 21. Current market price: $21.78, TCGplayer market prices via Scryfall.
Prevent the next X damage that would be dealt to any target this turn. Until end of turn, you may pay {1} any time you could cast an instant. If you do, prevent the next 1 damage that would be dealt to that permanent or player this turn.