Kalitas, Traitor of Ghet

The death-replacement clause is the entire engine, and it does two jobs at once that black almost never gets to combine. Against an aggressive board it punishes attacking and trading: every nontoken creature your opponent loses leaves play permanently (exiled, not buried, so it dodges every recursion plan they had) and hands you a 2/2 in the bargain, swinging the parity of a single combat by two bodies. The exile rider also starves any plan that wants those creatures back in the yard: reanimation, recursion, and death triggers all whiff because the card is gone rather than dead. The Zombies aren't just chump fodder, either. The sacrifice ability eats your own Vampires and Zombies to grow Kalitas, so the tokens it manufactures become fuel for its own size, a closed loop that converts your opponent's losses into your clock. That self-feeding line is what separates this from the long line of black lifelinkers whose ability ends at "gains you life." Lifelink on a 3/4 stabilizes; the death-replacement turns stabilizing into snowballing, and because neither ability carries a tap symbol or a summoning-sickness clause, both come online the instant Kalitas resolves. The four-mana body is the only thing keeping it fair: four toughness dies to most premium removal, so the whole plan hinges on whether the opponent has an answer in hand. Land it into an open board and it rewrites every creature interaction for the rest of the game, which is why a card with a fragile back end stayed a fixture wherever grindy black midrange lives.