Dead-Iron Sledge

In Commander, Dead-Iron Sledge earns its slot in equipment-matters decks and in any shell that wants to trade creatures efficiently — slap it on a token or a utility creature and suddenly every attacker or blocker your opponent points at it becomes a liability. Legacy and Vintage have faster, more broken things happening, so Dead-Iron Sledge rarely shows up there outside of highly specific equipment synergy builds where the one-mana cost is the draw. Modern is the same story: the effect is real but the format's speed and the prevalence of enter-the-battlefield value creatures means mutual destruction often punishes you as much as your opponent. Commander is simply the best home — the slower pace, bigger board states, and prevalence of voltron or Stax strategies let Dead-Iron Sledge do exactly what it promises every game.