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, or Fetid Heath helps white-black decks turn an available white or black mana into a useful pair of colored mana. Pay one of those colors and tap Heath to produce two white, two black, or one of each. This can help satisfy demanding costs such as double white or double black without requiring every other land to produce that exact combination.
Godless Shrine is a flexible partner because either of its colors can fund the filter ability. Heath also taps for colorless on its own, but it cannot create colored mana without the initial white or black input. Filtering is not extra ramp: the two lands or sources together normally still supply two mana rather than three.
Plan the turn around both the amount of mana available and the colors each spell requires. A hand containing Sol Ring can have plenty of total mana while still struggling with colored symbols. Keep reliable lands alongside specialized sources, and sequence the source that establishes a missing color before committing resources to a payoff that depends on it.
Heath is especially helpful when a list mixes demanding white and black costs instead of relying mostly on generic payments. Its weakness is a hand with no colored input. Pair it with dependable white or black sources and avoid counting its filter ability as independent first-turn color access.
