Dual Avatar Invitation X SPELL Discard 1 card, and if you do, Special Summon as many "Dual Avatar Spirit Tokens" as possible (Warrior/LIGHT/Level 2/ATK 0/DEF 0), also for the rest of this turn you cannot Special Summon monsters from the Extra Deck, except Fusion Monsters, and all Tokens you control cannot be Tributed and are destroyed during the End Phase
Then you spend 7 mana (doable with the mana ramp here) to discard X cards and exile that many from a foe's library and then play them for free
Will the Citadel player run out of targets or life before they find their wincon
Lands like Fabled Passage and Evolving Wilds could trigger Moraug twice, too, providing you with another combat phase on top of the first two
Considering you need to have no monsters and no cards in your hand, there would be no need to mark as you would have literally nothing
Reckoner Bankbuster has been the de facto draw card for black-white midrange and control decks ever since it saw release, and this isn't about to change anytime soon