In exchange, he required not gold or blood but commitment. He demanded that towns stop dumping certain poisons into the waterways, that industries adopt cleaner practices, that fishing seasons respect spawning migrations. The bargains were enforced by subtle, ocean-born punishments: a die-off of a favored species that resumed only when pledges were kept, or fogs that hid trade routes until polluters mended their ways. Some saw coercion; others a stern teacher. Either way, the bargain reshaped human economies, pushing them—by decree of tide and taste—toward sustainability.