Echo of Dusk

The counting method is where this design earns its keep: Descend 4 tallies permanent cards in the graveyard specifically, so the instants and sorceries most black decks spill into their yards do nothing to switch it on. That distinction is the whole point. A two-drop that grows into a 3/3 with lifelink is a real payoff for the slot, and pricing the condition to permanent cards forces you to commit to a permanents-heavy graveyard rather than backing into the bonus off any spells you happen to cast. The lifelink names the shell: a self-sacrifice or attrition build that trades bodies all game and wants to stay above the curve on life, not a tempo deck that empties its hand and never looks back. Because the bonus is a static ability, it flips on and off with the graveyard state, so a well-timed exile effect from an opponent can shrink the body back to a 2/2 mid-combat, and a fresh fetch-and-sac or a creature dying can restore it just as quickly. Self-mill, sacrifice, and combat losses all feed the count without asking you to warp your spell base, which is the cleaner version of the old graveyard-quota idea: permanents are exactly the resource a grindy black deck is already generating, so the quota reads as a natural accumulation rather than a deckbuilding tax.