Herd Heirloom [Tarkir: Dragonstorm Promos]

Set: Tarkir: Dragonstorm Promos Type: Artifact Rarity: Rare Cost: {1}{G} {T}: Add one mana of any color. Spend this mana only to cast a creature spell.{T}: Until end of turn, target creature you control with power 4 or greater gains trample and "Whenever this creature deals combat damage to a player, draw a card."