Whip of Erebos [Theros] Arkhos where X is that spell's

where X is that spell's mana value

"Monsters dwell in every heart

Set: Fourth Edition Type: Artifact Rarity: Rare Cost: {1} Mana Vault doesn't untap during your untap step

Set: Oath of the Gatewatch Type: Sorcery Rarity: Uncommon Cost: {2}{R} As an additional cost to cast this spell

Whip of Erebos [Theros] Arkhos where X is that spell'sSet: Theros Type: Legendary Enchantment Artifact Rarity: Rare Cost: {2}{B}{B} Creatures you control have lifelink. {2}{B}{B}, {T}: Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step. If it would leave the battlefield, exile it instead of putting it anywhere else. Activate only as a sorcery.