Bucolic Ranch

A tribal land built for a creature type that barely existed as a mechanical category before Mounts formalized it, and every clause is bent toward that single archetype. The colorless tap gives it a floor when your Mounts are stuck in the graveyard and you just need a land to make mana; the any-color mode is the real fixing, walled off so tightly that the mana it produces can pay for a Mount and nothing else. The third ability is where the card earns its build-around status: a repeatable filtering engine that digs for Mount cards specifically, letting you convert flooded late turns into gas as long as your deck is dense enough with the right type to make the three-mana whack-a-mole worth it. That density requirement is the whole bargain. A generic top-of-library dig at this rate would be unremarkable; restricting the reveal to a narrow creature type turns it into a payoff only a committed Mount deck activates consistently, and it comes stapled to a Desert, so it feeds any card that cares about that land subtype. This is design that lives or dies by how many Mounts see print: a support piece whose ceiling is set entirely by the pool of things it is allowed to find, and whose floor is a color-consistency compromise you accept because the upside justifies running a source that only produces filtered mana for one narrow purpose.