Annul

The narrow counterspell lives or dies by what the other deck is built around, and this is the cleanest example of the type: one mana to stop an artifact or enchantment spell, and nothing else on the stack. The tradeoff is explicit. Counterspell proper costs double and answers anything; this halves the price and hands back most of the targets. What the discount buys is a hard answer to two permanent classes that other colors cannot interact with at the same point in the spell's life. Blue does not destroy an enchantment once it resolves, so the leverage is the timing window: catch the spell before it lands and a single mana neutralizes something that might otherwise demand a dedicated removal slot. The friction is just as plain. Against a deck running no artifacts or enchantments it counters nothing, and that blankness is the permanent risk of any answer this specific. The bet is placed at deckbuilding, before a single card has resolved, because a counterspell never touches the battlefield to begin with. That tension between rate and applicability defines the slot: a sideboard-shaped effect printed at maindeck efficiency, waiting for an opponent whose plan routes through a permanent it can name. It has been reprinted steadily across the years, always doing the same job, always priced as cheaply as a counter reasonably can be, because the restriction is what makes one mana fair.