Bringer of the White Dawn

The printed nine-mana cost is the misdirection: nobody assembles seven generic and double white for this, because the alternative payment of one mana of each color is the entire point, the convergence ritual every member of its cycle shares. That requirement is the actual design tension. A card that presents as the white pillar of a five-color value experiment is really asking you to build all five colors into your manabase before it ever resolves, then handing you the most reliably abusive of the five payoffs. Where its siblings bounce or burn or draw, white's job here is permanence: a 5/5 trampling body that, at the beginning of your own upkeep, reanimates whatever artifact your graveyard is hiding, with no rarity or cost ceiling on what comes back. A mana rock, a Triskelion, a Wurmcoil Engine, all returned free, on a clock that only steepens as the yard fills. The friction holding the rate together is twofold: the convergence cost up front, and the once-per-cycle timing that gives an opponent a full turn to find an answer before the engine compounds. Trigger it on every player's upkeep instead of just yours and the loop would tip from strong to indefensible; restricted to your own, it stays a payoff you have to earn the manabase for first, then keep alive to collect.