Abolish

The pitch mechanic is the whole point: ditch a Plains and the artifact or enchantment dies without paying a single mana. That trade was the throughline of a free-spell cycle from an early era, where each color got an instant you could cast by discarding a same-typed land instead of paying its cost. The discipline is real, just inverted from how it first reads: the alternative cost buys you tempo (an instant-speed answer for zero mana, on a turn when your lands are already committed elsewhere) at the price of card advantage. You spend two cards, the answer and the Plains, to resolve one, and that two-for-one exchange is the tax the free cast pays back. What makes this version durable is that it folds two answers into one slot. The mode you want against an artifact and the mode you want against an enchantment live on the same card, so the pitch line lets you develop your turn normally and then break parity the instant the threat resolves. White has always had clean disenchant effects: Disenchant itself sets the baseline rate. The alternative-cost clause is the design move that matters, because it lets the card answer a threat at exactly the moment it lands without ever asking you to leave mana untapped, as long as your manabase runs the Plains to feed it.