mtg horror commander precon Magic: The Gathering Duskmourn: House of Deck Bundle identifying it as a valuable addition to their collections CLB] Commander Precon Face Cards

Enervate, meet Arc Lightning as an instant

Looking back now, 5 mana is an awful lot to ask of an enchantment that doesnt do anything when it enters the battlefield, but if allowed to sit on the battlefield after a board wipe or a couple turns of play from an Aristocrats strategy (decks that derive value from sacrificing creatures), Black Market can quickly generate game-winning amounts of black mana

Almost instantly, all the sets products sold out everywhere, which is practically unheard of for MTG

If you only make one change, make it this

Both also mentioned an an additional Qualifier Side Event on the second day

For two black mana, you can destroy any target creature without the worry of it coming back through regeneration