Infest

The number that matters here is two. A symmetrical -2/-2 lands at the exact toughness band where aggressive starts live: the one-drops, the two-drops, the small evasive bodies that decks lean on to close games early. Above that line, the spell shrinks toward irrelevance; a board of three-toughness midrange creatures shrugs it off entirely. That ceiling is the whole pricing argument. Black gets a cheap, clean way to unmake an entire low curve in one card, and pays for it with a hard cap on what it can kill. Compare the work to a one-sided sweeper like Crux of Fate or a scaling Toxic Deluge: those answer the whole board for a premium, while this answers only the bottom of it for three mana. The interaction worth knowing is that the modifier is permanent until end of turn and stacks, so a follow-up shrink finishes off whatever survived the first pass, and any creature that was already damaged this turn dies to a smaller reduction than its printed toughness suggests. Played proactively, it reads as a punishing answer to a fast, flat-curved aggro draw; played reactively against a token deck, it is closer to a wrath. The design has been revisited many times since, but the core lesson is the one Infest states plainly: a tuned, narrow sweeper that only ever kills small things can still be a centerpiece against the decks built entirely out of small things.