Vampire Nighthawk

Three keywords stacked on one body, and the design's elegance is how each one covers a gap the others leave open. Deathtouch turns a modest 2/3 into a tax on attacking: any creature that swings into it trades down, since one point of damage from the Nighthawk destroys whatever it touches, even a 6/6. The exchange runs both ways, though, with no first strike or indestructible to protect it, so it dies right alongside the thing it kills: a deterrent that trades one-for-one rather than a wall that survives. Flying converts the same body into reliable offense, because the creature that needs to connect for lifelink to matter usually can. And lifelink quietly buoys the life total each combat, letting a deck that has raced itself low stabilize behind a flier the opponent cannot profitably block. The deathtouch-plus-flying pairing is what designers kept returning to: a deathtouch flier doubles as one-card air defense, threatening to trade with anything that goes over the top while pressuring the ground from above. The rate set a template that later black two- and three-drops have been measured against, and most imitators give something up (a worse body, fewer keywords, an extra mana) to assemble the same package. The double-black cost ties it to black-heavy decks, ruling out any wider splash. It reads as unremarkable on paper and plays as a clock and a life-swing engine at once, which is why it keeps getting reprinted as the reference point for an efficient evasive black creature.