For the immediate threat, I think it would be fun if we're not<em>directly</em>battling the power pools at the start, but something that was kicked in motion by the interaction of the power pools. Like an angry god who was displaced by a flood and wants to conquer/convert a new realm, or a civil war as a region tries to consolidate before the Crusade of Uniformity arrives, but also the civil war is fueled by the Silken. Or the Uniformity absorbed the monks who used to cleanse the waters that run off the mountain-sized corpse of the demon god and now there's a plague of madness downriver.