Arvinox, the Mind Flail Scryfall ID_90f8de01-c1bd-4533-9e98-61e7d25dcf88 and your straw hat is

and your straw hat is the largest the world has ever known

Return all creature and planeswalker cards with mana value X or less from your graveyard to the battlefield

When Symbiotic Wurm dies

14 Magic: The Gathering cards

Arvinox, the Mind Flail Scryfall ID_90f8de01-c1bd-4533-9e98-61e7d25dcf88 and your straw hat isArvinox, the Mind Flail Legendary Enchantment Creature Horror 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 mana of any color to cast those spells. Set: