Hellrider

The math is the engine: every attacker is worth a point straight to the player or planeswalker it's attacking, on top of whatever it deals in combat, and that point is locked in the moment creatures are declared, before blocks are even an option. A board that can't profitably swing on the ground still drains the opponent just by attacking into it, which turns chump-blocked alpha strikes lethal regardless of how the combat math resolves. The reach lands during the declaration step, before the defender gets to make a single decision; that's the difference between this and a damage-doubler, which only pays out after blocks. Pair it with a token-maker or a sacrifice-fueled go-wide plan and the body almost stops mattering; haste means it starts counting the turn it lands. The 3/3 frame is the limiter, dying to most removal, but the deck that wants this wants ten creatures already on the table, and the trigger needs that crowd to do its work: an empty board generates nothing, while a flooded one converts every body into guaranteed damage the moment it swings. That dependency is the whole shape of the design. This is red's cleanest argument that going wide should be punishing on its own terms, separate from how big anything hits. The reward goes to the side that has already won the board-building war, and the question it poses to the defender is not whether they survive the combat but whether they survive the attack step itself.