Descolada is a Layer of the Abyss, known to sages as the Second Layer
A vast, possibly infinite maze of tunnels crafted by deadly insectile races, the Driller's Hives were the first layer beyond Pazunia to be catalogued by the Fraternity of Order, and as such this layer is recorded in the Lexicon of the Abyss as the second layer of the Abyss. Unluckily for the Guvners, the Driller's Hives are amongst one of the deadliest layers of the Abyss. Not only are its inhabitants virulently against any but their own kind, but the very air seems to be infected with a disease that will cause any being of flesh, living or dead, to decompose into innumerous insect eggs within a matter of hours.
The destination for the initial expedition, as the first step into Factol Clarille's great endeavor, was selected as having the most interesting potential among those of Cabiri's abandoned scrying portals that the faction was able to unlock; of course, while they did spy the natives, they had no means of detecting the virulent disease that infests every corner of the layer. Seeking to have the greatest chance of success, they ensured that it would only take place following six months of preparation, training, and study, using the best of the disorganized and scattered lore on the Abyss that existed up to that point. The initial expedition consisted of four teams of twenty sages and combatants each, each team hand-selected by one of Sigil's then-leading experts on the Abyss: Andor Damodred and Lord-Provost Carolon, both of the Fraternity of Order; Harldin Jhondar, independent Sigilian mercenary; and the priestess Masema Larisett of Lolth.
Of the four expeditionary teams, within three hours all but the Lord-Provost's had been killed, and of that team a full eleven of its members succumbed to the disease; despite what healing magic the teams could bring to bear, only Carolan himself and his eight fellow paladins managed to escape, their bodies studded with deep wounds left by the local creatures; of those eight, three perished within a week of returning, succumbing to the damage inflicted on both their bodies and their minds. Sir Carlon himself was never the same, accepting a quiet transfer to the Fortress of Disciplined Enlightenment following the bloodbath. As a result, the layer soon became the first to be put under Fraternity interdiction; so disasterous was it, even, that Factol Clarille suspended all planned further expeditions, and work on the Lexicon did not continue for a further seven years, with questions circling for that entire time if it would ever be resumed.
Those that managed to return were changed by their experience, the horrors of the plane and the unearthly nature of the inhabitants both wearing down their sanity; they still held themselves enough to tell stories of the vicious natives, a blend of ant, spider, scorpion, and wasp since identified as the obyrith race known as the ekolid. The layer is ruled by the ekolid-like obyrith lord Tharzax, thought to potentially be a former rival of Cabiri. The entire layer, so far as its few incursions have revealed, consists of the hives of ekolid, abyssal ants, twisted versions of formians and abiels, and likely other insectile beings, with no sites of note.
Upon setting foot in the Driller's Hives, a person is instantly infected with this transformative disease. Once infected, the victim must make a Fortitude save once every 10 minutes at DC 20; failure of this save inflicts 1d4 points of Constitution damage (or Charisma damage if the victim is undead). Upon reaching 0 Constitution (or Charisma), the victim dies, their body decomposing into hundreds of ekolid egg sacs as described in that creature's stat block. This disease can be cured with remove disease or other similar enchantments, but for obvious reasons using such spells is useless while the victim remains within the layer.
Descolada is a warm humid layer. Much of the Layer are warm, wet, tropical jungles, with some pockets of flat rocky plains and towering mountains.