Underworld Breach (Extended) [Theros Beyond Death] ARC129-R legendaries

legendaries

where X is twice the number of artifacts you control

then put all cards exiled with Knowledge Vault into their owner's hand

If that mana is spent on an instant or sorcery spell

Set: From the Vault: Twenty Type: Legendary Creature — Rat Ninja Rarity: Mythic Cost: {4}{B}{B} Ninjutsu {3}{B}{B} ({3}{B}{B}

Underworld Breach (Extended) [Theros Beyond Death] ARC129-R legendariesSet: Theros Beyond Death Type: Enchantment Rarity: Rare Cost: {1}{R} Each nonland card in your graveyard has escape. The escape cost is equal to the card's mana cost plus exile three other cards from your graveyard. (You may cast cards from your graveyard for their escape cost.) At the beginning of the end step, sacrifice Underworld Breach.