Unstable Mutation [Arabian Nights] Gatecrash Set: Kaladesh Promos Type: Artifact

Set: Kaladesh Promos Type: Artifact Rare Cost: {4} Whenever you cast a spell

Set: Urza's Destiny Type: Enchantment Rare Cost: {2}{W}{W} Each other non-Aura enchantment is a creature in addition to its other types and has base power and base toughness each equal to its converted mana cost

Whenever a Mountain enters the battlefield under your control

Just hope yours isn't full of coal golems

The Nightmare arises from its lair in the swamps

Unstable Mutation [Arabian Nights] Gatecrash Set: Kaladesh Promos Type: ArtifactSet: Arabian Nights Type: Enchantment Aura Common Cost: {U} Enchant creature Enchanted creature gets +3 +3. At the beginning of the upkeep of enchanted creature's controller, put a 1 1 counter on that creature.