Braids, Arisen Nightmare (Showcase) [Dominaria United] Human Druid Knight and you may spend mana

and you may spend mana as though it were mana of any color to cast

you may have it fight Grothama

When Necromancy enters the battlefield

Set: Mercadian Masques Type: Creature — Human Pirate Rarity: Rare Cost: {4}{U} Flying

Set: Ravnica: City of Guilds Type: Enchantment Rarity: Rare Cost: {2}{G/W}{G/W}{G/W} ({G/W} can be paid with either {G} or {W}

Braids, Arisen Nightmare (Showcase) [Dominaria United] Human Druid Knight and you may spend manaSet: Dominaria United Type: Legendary Creature Nightmare Rarity: Rare Cost: {1}{B}{B} At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.