Cinderfall Vale

If a visitor was asked to describe the greater area of the region, many would quickly settle on the term "Beautiful Hellhole." A collection of forests, hills, and marshes, all steeped in blackened wood, rolling grey ash, and a brilliant riot of oranges, yellows, and reds.  The few biomes within the region are small and varied, and while they have significant differences, they share more than a few omnipresent hazards. In particular, the blazing nocturnal 'Fireflies' form an omnipresent threat and natural bulwark, helping isolate the region from the outside world. It is not a place to be navigated without adequate preparation, and the only reason outsiders are able to traverse the region is the solitary winding road cutting through it's wilds.
The local timber in the region all share a trait common among the limited array of hardwood. It readily absorbs moisture and stubbornly retains water. It is strong, durable, and nigh-immune to fire when wet or damp, but becomes chalky and brittle when dry. Most practical use of the wood is limited to the region and it's high humidity and dense groundwater.
Cinderfall Forest
The western forest is known for it's oppressively hot and dry sauna-like environment. The great trees roots run deep, drawing moisture from the abundant aquifers below the ground. Thick carpets of ash and cinders bury the tangled roots, great boulders, and jagged stone. The smouldering carpet is soft and spongy - almost silky to the touch, but poses it's own hazards, for the winds can kick up blinding storms of ash. The flies nest within the trees and feed within the carpets below during the day. Furthermore, the trees are always making new leaves, for they quickly wither. The days are usually clear or have small amounts of ephemeral smoke that does little more than give the area a slight, campfire scent. But there are days when a great many leaves fall, and a dense blanket of black, suffocating smoke covers the area as the Fireflys stir below and swarm upon the fresh leaves.
Blighted Rift
The swamp is treacherous enough with the risk of boiling mires, but pools of acid, caustic liquids, and murky oils add to an already treacherous area. Great spires of salts, tars, and dampened ash form the bulk of sparse, traversal ground. And what isn't a boiling, chemical wreck is quickly taken over by dense, hazardous vegetation. Bladed, metallic grasses, stony trees, and other twisted and borderline supernatural vegetation lingers in the toxic mists of this gruesome pit.
Black Dunes
This hilly region is the closest thing to open ground Cinderfall has. Great piles of ash and charcoal litter the earth among the odd boulder or glassy spire. The appearance of the region isn't far from the classical bleak and blackened hellscape. Even the warm orange of burning coals and grey ash is absent from the dark dunes. 
Emberwood
The eastern forest provides it's own unique brand of oppressively wet heat along with a riot of color unlike the rest of the region. The ground is a mix of steamy springs, dense soils, and rocky slabs. This area manages to house small thickets of reedy grasses of blackish greens and deep ebon blues which help break up the reds and oranges and yellows of the fallen leaves among the scorched stones. The larval fireflies here swim about in the scattered pools of water and the occasional spring. When that is combined with the broad leaves of the trees, you have the ideal conditions for thick blanket of omnipresent steam which shrouds the wood.
'Cinderfall Steppe'
The most merciful of biome of the entire region, the Steppe is home to a combination of springs, gysers, and blackish grass dotted marred with the occasional explosion of fiery color from the region's shrubs. Near the mountains, nestled within mouth of a valley is the city, Burned Waters 
Natural Hazards
Fireflies
If these small insectile bastards didn't exist, this region wouldn't be such a death-sentance to the majority of mortal life.There's more than a few subspecies with unique adaptations to the various biomes, but they all share a few common traits. Adult beetles swarm like locusts and incinerate anything without the slightest protection or resistance to fire. It's not known exactly how they feed, but it is speculated to involve a combination of combustion and the ambient magic which teems within the borders of Cinderfall.
Magewither
While the name is somewhat misleading, it's simply the local title given to a sort of sickness tied within the rich, ambient magic within the region. The cause involves an irregular flow of magic from the body to and from the surrounding enviornment, and can afflict more than just spellcasters, with symptoms being quite similar to Altitude Sickness. Either too much magic enters the body, or the body holds too little magic, in which case the individual as magic attempts to reach an equilibrium.