Paladin Danse, Steel Maverick
The self-sacrifice is the whole design logic here. A 3/3 with vigilance and lifelink for three mana is a defensible, self-sustaining body, but the activated ability asks you to trade that body away to grant indestructible to every creature you control that's an artifact or Human for a turn. That is a one-shot protection burst, not a repeatable engine: the moment you fire it, Danse leaves via exile, so there is no graveyard recursion to lean on and no way to hold the creature back for a rebuy. The clause that names artifacts and Humans is doing quiet double-duty. As a Synth Knight artifact creature, Danse would itself qualify for the protection if it stayed on the battlefield, which is precisely the tension the self-exile resolves: you spend the protector to save the protected. Structurally this is the same beat as a mass fog or a board-wipe blank, but stapled to a permanent that earns its keep as a beater first and becomes an escape hatch second. The reward for building around it is narrow by intent: stack your side with artifacts and Humans and Danse becomes an anti-sweeper, an alpha-strike enabler, a way to walk a swarm through a bad block. Build wide across other creature types and the button does nothing for most of your board, which is the cost of an effect that would be oppressive if it protected everything.

