Lifening Elemental is a rare Creature — Vampire Elemental card from Mystery Booster 2 (MB2), collector number 547. Current market price: $0.17, TCGplayer market prices via Scryfall.
Lifelink Splice onto instant or sorcery {1}{B} (As you cast an instant or sorcery spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's abilities to that spell. It's still an instant or sorcery spell.)