The Republic struggled to control its Sours. In the Zaibatsu, the souring had become epidemic. Mutant fungi had spread like oil slicks, forming a mycelial crust beneath the surface of the soil. This gummy crust repelled water, choking trees and grass. Dead vegetation was attacked by rot. The soil grew dry, the air grew damp, and mildew blossomed on dying fields and orchards, gray pinheads swarming into blotches of corruption, furred like lichen...