Lotus Field

The trick is in the arithmetic, and the arithmetic is deliberately a wash. Sacrificing two lands for one that taps for three of a single color nets you the same mana you would have had by simply playing a third land, at the cost of a card and a tempo hit while it sits tapped. On its own, that is a bad trade dressed up as ramp. The card is not built to be played on its own. It is a combo enabler that only turns a profit when paired with an untapper (any effect that lets it tap twice in a turn suddenly yields six mana of one color from one source) or when the lands feeding the sacrifice have already done their work in a graveyard-hungry deck. Hexproof is the clause that keeps the whole scheme from being suicidal: having concentrated your entire manabase into a single point of failure, the card refuses to let a Strip Mine or a targeted destruction spell convert your two-land sacrifice into a three-for-one blowout. It descends from the lineage of pain-first, burst-mana lands like City of Traitors and Ancient Tomb, but where those charge life or fizzle after a single explosive turn, this one charges cards up front for a source of monochromatic mana that never taps out of relevance. The sacrifice is not a drawback the card apologizes for; it is the entry fee to a manabase engineered to break, not to fix.