Restrain

Fog with a rider, sold one attacker at a time. This is a defensive cantrip from a school of design where a spell replaces itself so a narrow effect rides along at no cost in cards, making a situational ability easier to justify than the raw version. Where a true Fog stops the whole attack, this trades breadth for a single attacker and hands you a card for the trouble, a different bargain entirely. It is built to neutralize the one threat that matters (the lifelink finisher, the enchanted beater, the legend swinging in for lethal) rather than to buy a turn against a developed board. Cast at instant speed during the declare-attackers step, it leaves the creature tapped and committed while you draw into your next answer, and the prevention covers a double-strike attacker on both its hits. The honesty of the card lives in the word "combat": a damage-based removal spell or a sacrifice-for-damage effect walks right past it, since neither deals combat damage. That narrowness is why it stayed a defensive footnote. The self-replacing logic that makes a cantrip counterspell or a cantrip bounce spell worth running only holds when the underlying effect earns a card on its own. Restrain never had a body of work worth replacing itself for: single-target Fog is a half-measure most of the time, and the draw is too small a sweetener to change that math.