The vast stretch of fens and bogs north of the Howling Hills separates Blackmoor from the Wolf Nomads' lands and those of Iuz. Vast stocks of vile things dwell within these semi-frozen wastes: ice toads, swamp trolls, white dragons, and allegedly, many undead creatures. It is said that fiends in service of Iuz seek out such undead and bring them within Iuz's own lands. It is also said that priests of Iuz learn the secrets of controlling malign, freezing fogs here. In these days, there is hardly a surplus of on-the-spot commentators to give reliable information about such matters.
A broad shallow swamp, teaming with reptile life, the Mist Marsh fills the lowlands west of the Cairn Hills. Lizardfolk claim certain areas of the deep marsh and wandering ghoul packs are a threat throughout.
The V-shaped swampland above the neck of the Tilvanot Peninsula is sunken in the center and cliffed along both coasts. This cupping causes water to form into standing pools and sluggish streams and flows. The resulting morass of water and vegetation is known as the Vast Swamp. The movement of water within it indicates that it generally drains southward. It must be that there are underground channels through which its outflow runs. On a limestone bed, clays, silts, and peat from decaying vegetation have produced a rich carpeting. Fabulous lilies, creepers, and ferns throng among swamp cypresses in the tea-colored waters.
The folk of Sunndi to the north regard the Vast Swamp with ambivalence. It is a great protection against land assault from the Scarlet Brotherhood, but it is disease-ridden and packed with hazards such as will o'wisps and many monsters. The gigantic crocodiles of the central swamp grow fat on a diet of bullywug and grung, but the numbers of those batrachians are almost beyond counting.
Lizard men and troglodytes compete for living space with the degenerate frog-folk, and all manner of poisonous toads, frogs, snakes, and insects add to the impressive range of unpleasant flora and fauna. These are said to be feral gray elves to the south, who are masters of vine-swinging above the virtually impassible swamp waters. There are many tales and legends concerning this area, especially in old times before the swamp was as extensive as it is now. The most oft-told one is that of the demilich Acererak, who is said to have ruled the swamp in the distant past and now has his burial place somewhere within its confines.
This comprises an extensive area of treacherous wetlands south of the Celadon Forest. Its bogs are avoided during summer, since they buzz with disease-carrying insects and are infested with poisonous reptiles. In the fall, however, harvests of reeds, rushes, and swamp hay are gathered by Nyrondese working from long, flat boats propelled with poles. Because of the poverty in Nyrond, desperate souls try fishing and trapping here, and the harvest of human meat happily eaten by alligators and scavengers, not to mention other monsters, looks to increase substantially.
The Hool River's meanderings along the level terrain separating the Yeomanry and the Sea Princes' lands are surrounded by quaking mires and almost bottomless pools. The marshes are full of natural hazards; a man can slip or fall to a watery, choking death in a few seconds. Only truly desperate human or humanoid renegades flee here, and the lizard men of the marsh are happy to eat them when they do. Lizard kings are said to have turned most of those reptilians to evil.
The Hool Marshes have their fair share of monsters. In the central marsh, northwest of Westkeep, there is said to be a community of yuan-ti with considerable magical powers who dwell within a temple which is itself magical. No reliable reports of this exist, however.
The mix of marshland, semi-scrub, and watery broadland has historically provided sanctuary to outlaw humans and demihumans fighting the evils of the Overking of Aerdy. Some have drifted back to Rel Astra now, but most stay to carry on their lives here. Unlike most areas of this sort, evil things fear to enter the trackless Lone Heath, where there is said to be an alliance of druids and rangers which has close links with those of the Grandwood Forest.
These unhealthy stretches along the northern coastline of Hepmonaland are almost unexplored, but the meager accounts of the place are fairly consistent. It is home to many exotic birds and insects, whose weathers and chitin would propably fetch good prices if they could be exploited. Giant crocodiles and poisonous reptiles and amphibians throng the place. There is said to be an extended family of black dragons (a most unusual occurrence) in one central location. The flora is similarly said to be exotic and dangerous, with carnivorous plants and huge flowers, pitcher plants, and giant ferns standing twice the height of a man and more.
Separating Gran March and Keoland, these marshes are slowly receding as determined efforts are made to drain them and claim the fertile land for arable farming. Swamp otyughs, numerous reptiles, and lizard men are among the major fauna of the marshes here. These marshes contain a very tall rush with a stalk as thick and tough as bamboo, which is valued for building animal pens and even stockades.
These fens are well named, for all manner of fierce and gigantic trolls, ogres, gnolls and their ilk prowl the desolate wastes of this fell place. The fens are always misty - clouds and swirls of chilling fog drift down from the Griffs and Rakers at the head of the Yol River and settle on the Troll Fens. The Theocracy of the Pale hedges the area with watchtowers, keeps, and three great castles, watching for unwelcome visits from the monsters of this dire place.