Defense of the Heart [Mystery Booster] 226 Set: Return to Ravnica Type:

Set: Return to Ravnica Type: Creature — Dragon Rarity: Mythic Cost: {6}{R}{R} Flying

Set: Black & White: Boundaries Crossed Type: Item Rarity: Rare Ace

−5: Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn

Set: Black & White: Next Destinies Type: Psychic Rarity: Holo Rare Retreat cost: Colorless

it becomes an Aura with "enchant creature put onto the battlefield with Necromancy

Defense of the Heart [Mystery Booster] 226 Set: Return to Ravnica Type:Set: Mystery Booster Type: Enchantment Rarity: Rare Cost: {3}{G} At the beginning of your upkeep, if an opponent controls three or more creatures, sacrifice Defense of the Heart, search your library for up to two creature cards, put those cards onto the battlefield, then shuffle.