Rockslide Ambush

The damage scales with your Mountains, which turns two-mana removal into a referendum on how committed you are to red. In a board built around the subtype it can clear nearly anything; in a deck splashing red over two or three colors it shrinks toward irrelevance. That conditional payoff is the whole bargain: cheap to cast, but only worth casting if you have built the manabase that earns it. Crucially, it counts any land carrying the Mountain subtype, not just basics, so dual lands, shocks, and triomes all feed the number. That detail softens the ask in modern manabases, where fetchable Mountain-typed duals let you chase devotion without surrendering your color options entirely; the spell's ceiling is therefore more accessible than the floor suggests. It belongs to a small family of red removal that asks you to count your own lands before you fire it, expressing single-color devotion through land totals rather than colored pips, the way red has always preferred to measure its own commitment. The high end and the low end sit far apart, and the design makes no attempt to narrow the gap; this is a spell for the player who has already decided to lean on the mountain, not the one keeping options open.