Demonic Embrace

The graveyard clause is the whole engine, and the discard cost is the toll that stops it from being free recursion. Auras have always fought a card-disadvantage problem: spend a card, enchant a creature, and a single removal spell two-for-ones you. This one answers that math directly by letting the Aura come back after it dies with its host, but it prices the return in life and a card from hand rather than mana alone. That turns it into a recursive threat that also feeds discard-matters and graveyard-matters strategies: the discard is not just a tax, it is fuel for anything that wants cards in the bin or cards leaving your hand. The +3/+1 and flying make it a finisher on a small body, so the pattern it rewards is a low-to-the-ground black deck that empties its hand fast and then buys the Embrace back out of the yard as a repeatable evasive clock. Making the enchanted creature a Demon is mostly flavor, though it quietly turns a token or a mana dork into something a tribal payoff might notice. The lift over an ordinary pump Aura is that the card is never truly dead: chump it into a blocker, sacrifice the creature, let removal answer it, and it is still sitting in the graveyard asking to be spent again.