Mind Flayer, the Shadow [Secret Lair Drop Series] Genestealer Cults if that spell's mana cost

if that spell's mana cost or that ability's activation cost contains {X}

and research

Set: Born of the Gods Tokens Type: Token Artifact — Gold Rarity: Common Sacrifice this artifact: Add one mana of any color

As a senior officer of the Skitarii

Mind Flayer, the Shadow [Secret Lair Drop Series] Genestealer Cults if that spell's mana costSet: Secret Lair Drop Series Type: Legendary Enchantment Creature Horror Rarity: Mythic Cost: {4}{B}{B}{B} Arvinox, the Mind Flail isn't a creature unless you control three or more permanents you don't own. At the beginning of your end step, exile the bottom card of each opponent's library face down. For as long as those cards remain exiled, you may look at them, you may cast permanent spells from among them, and you may spend mana as though it were