Here's the battle map. Listen and Spots checks needed to try to find your foe in the foggy haze. The wind is roughly 10 to 15 miles/per hour, and the wind constantly shifts direction, which causes the haze to swirl around you. I have noted the various terrain types on the map.
In any
corrupted areas, the PCs protective items will quickly begin to degrade: three times as fast. In the verdant hills directly south of the PCs, the degradation is halved.
The terrain noted as fissures are considered to be impassible unless Jump checks are made. Also, DC 10 Balance checks are required within 5 feet of the fissures or the ground will crack and a character will fall in. The smaller fissures are 10 feet deep. The larger/longer fissures are at least 20 feet deep.
The burning pits are filled with a caustic lava that does half fire damage and half acid damage if a character falls into one. The molten crags spew this same acidic lava into the air every 1d2+1 rounds, which hits everything within a 10-foot radius.
All the grassland and shrubland terrain is
easily ignited by flames. The badlands areas are less prone to catch on fire.