Invigorate is a common Instant card from Duel Decks Anthology: Garruk vs. Liliana (GVL), collector number 19. Current market price: $0.33, TCGplayer market prices via Scryfall.
If you control a Forest, rather than pay this spell's mana cost, you may have an opponent gain 3 life. Target creature gets +4/+4 until end of turn.
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