Jace, Wielder of Mysteries

Mill has always been a strategy that punishes its own pilot: a slow clock that fills the opponent's graveyard with fuel and usually runs the mill player out of cards first. The static ability rewrites the losing condition itself. Emptying your own library, the thing every deck spends the game avoiding, becomes the win. The +1 is the engine that gets you there under your own power: it mills a target (yourself, if you like) for two and draws a card on top, so each activation both feeds the graveyard and nets raw card advantage while thinning the library toward zero. The −8 is the payoff button: seven cards deep, and if that drains the tank, the game ends on the spot. What makes this a genuine self-mill finisher rather than a novelty is that the win check keys off drawing from an empty library, so it does not require the ultimate at all. Any effect that forces a draw with no cards left closes the game, which folds the planeswalker into a broader lineage of decking-as-victory pieces (Laboratory Maniac, Thassa's Oracle) while adding a loyalty engine that assembles the condition on its own. The design turns Magic's most maligned mechanic into a resource you spend deliberately, and the four-loyalty body absorbs enough pressure to buy the turns it takes to bottom out your deck on purpose.