| Category | Ruins |
| Continent | Karterus |
| Region | Azrik |
| Built | 16 Warper 410 |
| Map | Vetoubahr |
Thegildreon is an ancient, dilapidated stronghold located in the Broken Lands. This edifice was a grandiose temple constructed by the Melephaeusans, dedicated to the elven god Corellon. When the region was devastated by the Gulimbor Cataclysm (996 - 1203), a large group of Corellon's devout followers remained behind to safeguard the place. It was assumed they perished in the ensuing catastrophe, but a yuan-ti seer from Phlem claims a more sinister fate befell them. His writings in the tome *The Thegildreon Gateway* assert that the Gulimbor Cataclysm opened a rift to an abyssal world under the sway of Demogorgon. On the plane of Bal-Kriav, this rift manifested in the catacombs of Thegildreon. Secretly, succubi agents of this demon lord infiltrated the complex, subverting some of the priests. The aftermath was murder and the damning of the place, as all manner of atrocities were perpetrated by elves and demons. The temple became a ruin, a nightmarish, cursed place.
In 1130, the Irastâ tribe ventured into the ruin during one of the Broken Lands' periodic magical storms. According to a tablet in the ruin, written before the Irastâ were transformed into monstrosities, the temple's interior was in pristine condition, offering a welcome respite from the surrounding wasteland. A few years after the Irastâ's disappearance, Ba'lith's eastern frontier outpost came under attack by corrupted elderaunts speaking the demonic Abyssal tongue. The assailants referred to themselves as the Maleraunts.