Forbidden Orchard

A rainbow land that hands your opponent a 1/1 Spirit every time you tap it sounds like a pure liability, and in any deck that just wants colored mana, it is one. The gift is the point, though. By manufacturing a guaranteed opposing body, the Spirit token satisfies an entire class of effects gated behind "an opponent controls a creature," and that precondition has made this the canonical setup land for several engines. Oath of Druids wants the opponent to have more creatures than you before it goes off; Defense of the Heart checks for three opposing creatures; edict and theft lines need a legal target to point at. Forbidding nothing of its own, the Orchard supplies all of those triggers on demand by authoring a board state for the other player. The fixing is real and gets used, but the Spirit is the engine, and a deck that runs this is built to capitalize on creatures it deliberately gives away. That inversion is the whole appeal of the design, a downside land that does you no favors in a vacuum and a great deal once the shell is constructed to exploit the very tokens crossing the table.