Sultai Emissary

The death trigger is the whole point: a 1/1 that costs two mana and dies all the time, by design, because dying is when it pays out. Manifest off the top of the library means the replacement is a 2/2 (already a stat upgrade on the body that died), with a hidden upside attached: if the manifested card is a creature, it can flip face up for its mana cost at any time, turning a chump-block into a tempo swing the opponent cannot read in advance. That blind-flip incentive is what separates this from a plain death-replacement effect like the older bestow-and-token designs; manifest deliberately hides information, so the card rewards a deck that runs enough fat creatures up top that the face-down 2/2 is a threat rather than a placeholder. The friction is honest: half the time the top card is a land or a noncreature spell, and the manifest is just a vanilla 2/2 stuck face down forever, no flip available. A 1/1 that chump-blocks into a 2/2 with a coin-flip on a bigger creature underneath is exactly the kind of incremental, attrition-flavored payoff black has always traded in, and it asks the deckbuilder to weight the top of the library rather than the graveyard, an unusual demand for a sacrifice-adjacent card.