Villainous Wealth

The wedge payoff that turns an opponent's deck into your spellbook. The structure is unusually mean for an X spell: the same X that scales how deep you dig into their library also gates how much you get to keep, so casting it for a small number exiles a shallow pile and frees only cheap junk, while casting it for a large number both peels a meaningful chunk off the top of their deck and unlocks anything sitting in it. That asymmetry is the whole strategic axis. You are not generating your own card advantage; you are converting theirs into yours, which makes it sharpest against decks stuffed with expensive payoffs and dullest against fast aggro that has nothing worth stealing back. Note the precise wording: the cards are exiled rather than milled, so they never touch a graveyard, and each cast is capped at mana value X or less, so a deck full of cheap interaction yields less raw value per card flipped than one top-heavy with bombs. It is sorcery-speed and reactive in flavor only, since it does nothing on your opponent's turn and rewards an open mana count you have spent the game accumulating. The fantasy is theft on a grand scale, and the card honors it by asking you to be the player with the bigger mana engine, then spending all of it at once to cast your rival's best draws before they ever can.