Stun

The whole pitch is card-neutrality applied to a one-point combat swing. Stripping a blocker is a tempo play that ordinarily costs you a card for a single point of advantage, so the design answers the obvious objection by handing the card back: the one you spend is the one you draw. That refund turns "can't block this turn" from a situational alpha-strike enabler into something closer to a free action, letting you cycle through your deck while clearing a lane for an unblocked attacker or pushing through lethal. The instant-speed timing is the operative detail, because the effective window is the attack step before blockers are declared. Cast it then on the creature your opponent was lining up to block with, and that creature is taken out of the equation; the math they were about to do collapses, and you draw a fresh card. This is the early-era template for the cantripping trick, the same impulse that later produced effects designed to replace themselves rather than tax your hand. It does not generate card advantage; it preserves it, and for a one-point swing that distinction is the entire justification for the slot.