Sanguine Praetor

A board wipe disguised as a sacrifice outlet, and one that reads the curve rather than the battlefield. The activation is plain: pitch a creature, then every creature sharing its mana value dies, for one black mana a pop. Because the ability destroys each matching creature without targeting, it walks straight past hexproof and shroud, and it scales: feed it a one-drop and the mana dorks and aggressive openers fall together; feed it a five-drop and the midrange anchors go. The cruelty is in how creatures cluster around shared costs, so a single activation tends to clear a whole tier at once. The fuel is the constraint that keeps this from being a free symmetrical sweeper. Each activation demands a creature whose value matches what you want dead, so a pile of zero-cost tokens only ever clears other zero-cost bodies; you cannot point the engine wherever you like. The deckbuilding ask is therefore narrower than raw board width: you want expendable creatures spread across exactly the costs you intend to attack, and you want your survivors sitting at numbers theirs do not. Build the board so your pieces and theirs occupy different values, and the asymmetry becomes total, one mana value at a time, until the 7/5 itself is the last thing standing. The body is almost incidental; the real card is a repeatable, self-selecting sweeper that poses a single deckbuilding question and answers it in corpses.