Demon of Dark Schemes

The entry trigger and the energy mechanic are running on the same circuit, and that closed loop is the whole design. A six-mana Demon that wraths small creatures on the way down is a familiar shape; what sets this one apart is that the board sweep feeds the engine that recurs from it. The -2/-2 to every other creature clears the path, and each of those deaths hands you an energy counter, so the same trigger that empties the board simultaneously banks the fuel to repopulate it from below. The reanimation clause does not care whose graveyard it pulls from, which turns the symmetric sweep into a one-sided robbery: kill their creatures, harvest the energy, then drag the best of those corpses back onto your side tapped. Energy as a reanimation cost is the unusual move here, since it sidesteps the mana and life payments that usually price recursion and instead meters it to how much dying the board has done. Each reanimation costs four counters plus a three-mana activation, so the loop is gated by attrition rather than by raw mana, and the card rewards a board state already drowning in death triggers. It asks for a sacrifice shell or a grind-heavy build to keep the counters flowing, but where the deaths are plentiful, the Demon turns every one of them into both removal and resources, then a flier to close on what is left.