Sacrifice after III.) I For each player, exile up to one other target enchantment or creature that player controls until Vault 13 leaves the battlefield
The front face gets back a nonbattle permanent which is something that white and black can do when combined (white can get back artifacts, enchantments, lands, planeswalkers, and small creatures, while black can get back creatures of any size)
Still the power level of the effect is proven and Muse Seeker will open possibilities
This deck was already a fringe deck in Modern, but Oath of Nissa might be exactly what it needed to propel itself firmly into the sphere of competitive Modern decks, especially since this is another deck that can use the recent big mana offerings well and might want something like Ulamog, the Ceaseless Hunger or even World Breaker, both of which, of course, Oath of Nissa can help find when you need it, giving you a different sort of flexibility, offering a card that does what others couldnt
Your removal suite should also include cards that hit multiple targets at once
