The complete opposite of Phlegethos, Stygia was either a bottomless ocean covered by an ice sheet up to three miles (five kilometers) thick, or a frozen sea salted with huge icebergs buried in a cavern several miles/kilometers below Dis and hundreds of miles/kilometers away from fiery Phlegethos. The river Styx cuts across the ice forming a channel. It is also suggested that Styx supports small but hardy plants and mosses which, after millennia of decay of this vegetation, resulted in swampy areas along the banks of the river. A few floating islands were the only non-frozen ground in Stygia, their peaks wreathed in lightning arcing from the coal-black sky. Where lightning struck, a strange phenomenon called "cold fire" erupted: white flames of extreme cold that "burned" for a short time and then disappeared without a trace.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The great city of Tantlin was built upon one of these islands, in the curve of the swampy Styx, or perhaps on a giant ice floe. Due to the proximity of the Styx, Tantlin was a cross-planar trading post for those brave enough to attempt navigating the treacherous river.