Eternal Witness [Ultimate Box Topper] LED3-EN036 it becomes an Aura with

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

Set: Amonkhet Invocations Type: Legendary Creature — God Rarity: Mythic Cost: {3}{U}{B} At the beginning of your upkeep

but how could that be

Set: Happy Holidays Type: Enchantment Rarity: Mythic Cost: {B} {B}

Set: Friday Night Magic 2002 Type: Sorcery Rarity: Rare Cost: {X}{1}{B} Spend only black mana on X

Eternal Witness [Ultimate Box Topper] LED3-EN036 it becomes an Aura withSet: Ultimate Box Topper Type: Creature Human Shaman Rarity: Mythic Cost: {1}{G}{G} When Eternal Witness enters the battlefield, you may return target card from your graveyard to your hand.