Ephemerate (Etched Foil) [Strixhaven Mystical Archive] Fire[x2] you can activate it by

you can activate it by paying its energy cost and removing it and 1 blue card in your hand from the game

{1}{G}: Regenerate target creature

Even while overseeing many of Phyrexia's most important undertakings

Set: Collectors’ Edition Type: Artifact Rare Cost: {4} {4}

Ephemerate (Etched Foil) [Strixhaven Mystical Archive] Fire[x2] you can activate it bySet: Strixhaven Mystical Archive Type: Instant Rarity: Rare Cost: {W} Exile target creature you control, then return it to the battlefield under its owner's control. Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)