Porygon-Z (DP35) [Diamond & Pearl: Black Star Promos] Theros Beyond Death Promos Set: Limited Edition Alpha Type:

Set: Limited Edition Alpha Type: Enchantment — Aura Rare Cost: {B}{B} Enchant artifact At the beginning of the upkeep of enchanted artifact's controller

At the very least

Set: Fourth Edition Type: Artifact Rare Cost: {1} Mana Vault doesn't untap during your untap step

They each have flying and "This creature can't be enchanted

their majestic wings serve to circulate cool air through the vast hive chambers

Porygon-Z (DP35) [Diamond & Pearl: Black Star Promos] Theros Beyond Death Promos Set: Limited Edition Alpha Type:Set: Diamond & Pearl: Black Star Promos Type: Colorless Rarity: Black Star Promo Retreat cost: Colorless,Colorless