Tailfanged Adder

The glassification of the great northwest desert devastated its ecology over the last four centuries, converting all of the sand in this once-golden desert into a strange form of glass. However, in the years since it became known as the Glassed Expanse, it has developed its own subterranean ecosystem. Though the surface is inhospitable to nearly any form of life, a secret environment lurks barely a few meters down. The conversion from sand into glass simply rearranges the structure of the grains of sand, without producing any extra matter. Thus the melding of the sand particles together has left plenty of space beneath the surface, creating a vast and extensive system of small tunnels. This area was filled with the organic matter from the plants and fingi that previously lived in this arenaceous paradise. Many of the lifeforms that survived were in some way mutated or transformed by the process, as is often the case in areas affected by the "Imbued Enchantments" created by the Wyrmstalkers fighting against the Winged Tyrants. Some of the mutated fungi and bacteria thrived on this detritus, as did the organisms that fed on those, and what fed on those, and so on over four hundred years. An apex predator has emerged from this ecosystem. This creature can easily maneuver through the complex interconnecting tubules that exist beneath the surface, and can sense its prey through the vibrations of the fungus-lined glass around it. It's come known to be the tailfanged adder
The tailfanged adder is a powerful snake, thin enough to double back on itself in the tight confines of subterranean tunnels. Though nearly two feet in length, it is only one to two inches wide, and has very low bone density. This body formation allows it to easily weave through the complex system of tubules that expand beneath the surface of the glassed desert. Its most notable differentiation from the snakes that used to live in this desert is also its namesake. This creature has evolved an extra fang, one which can produce and inject an absurd volume of its venom, at the tip of its tail. This is likely used to strike at predators or prey that the adder senses approaching from the rear, as it would be too time consuming to turn around in a conventional way in such a confined space. This adaptation allows the adder to protect any single segment of tunnel that does not have a shaft intersecting it, creating a safe place in which to digest a meal or lay a clutch of eggs. In addition to its offensive capabilities, tailfanged adders have been discovered tapping or scraping this extra fang against the glass walls of the tunnels. This strange phenomenon might be used as a warning signal for others to stay away, or to mimic the walking pattern of small prey to attract its predators.