Mittentoe

What the Marshlands hide is even more fantastic than what the Alvenites think. Two millennia ago, a massive explosion below Loch Morgunt created a tidal wave that pushed most of the water of the underground hidden lochs to the surface.

This explosion was created when the underground laboratory of Archweaver Mintenwoe exploded and took out a sizeable portion of the underground ridge below Loch Morgunt. The explosion created a thick shelf of fused stones below the swamps, which makes it difficult for the waters to seep through to the layers below.

As a result, the Marshes are very susceptible to flooding. In addition, the uneven terrains and strange, sometimes magical, configuration of the ground layers are prone to create massive quick-sands, eddies and currents.

The remnant of Mintenwoe's warren-like complex is still yet to be discovered. However, as more and more expeditions are sent to the Marshes, it might not be long before some enterprising explorer and scientist discover the magical artefacts from that ancient time at the bottom of the swamps.

From the article 'The Putrid Tide'