Selfless Squire

The flash-in fog that punishes the swing. Hold it up, let the attacker commit, and cast it before the combat damage step: everything that would have connected with you gets prevented, and then the second trigger counts every point of that prevented damage and grows this Human Soldier by exactly that much. The fog half is the obvious draw, but the conversion clause gives the design its teeth, because it scales precisely with what the opponent chose to commit. The bigger the attack, the bigger the creature walking out the far side of combat. It rewards baiting: let the board build, let the math read lethal, then collapse the turn at the last responsible moment. What keeps it honest is the trigger's scope. It prevents damage dealt to you, not to your creatures, not to a planeswalker, so it does nothing against a sweeper and will not soak burn aimed at anything but your life total; it is a personal shield that pays itself back in stats. Flash is the load-bearing keyword. At sorcery speed this is a fragile 1/1 with a one-shot defensive ability and no surprise, telegraphed a full turn before it can matter. Cast on the opponent's turn, it becomes a combat ambush that ends the same attack it survives.