Jaws of Stone
Where Fireball spends mana to scale its damage, this spell spends land count, and the swap changes everything about how it lives in a deck. The damage equals the number of Mountains you control, so there is no mana sink and no diminishing return for splitting the load: every Mountain you have already deployed is free firepower the moment you reach six mana. That makes it a sorcery that wants a dedicated mono-red manabase rather than a generic burn shell, and it rewards flooding in a way most red cards punish. The free division clause matters just as much: X can be sprayed across multiple creatures, a creature and a face, or dumped entirely into one target, so a board of Mountains converts directly into a one-card removal sweep or a finisher depending on the turn. The cost structure is the discipline here. At it arrives late, by which point the Mountain count is also the thing that makes it lethal, so the card is balanced by its own clock: it only gets dangerous in the same game state where you have had time to build the lands that power it. It is a payoff for going wide on a single basic land type, the rare burn spell that scales with terrain instead of with the spell's own price tag.
