| Category | Ruins |
| Continent | Brucrumus |
| Region | Aerie of Dragons |
| Alias | Mud Wall |
| Built | 12 Kindle 775 |
| Map | Enkii Jusk |
The empire Thashangriel built Grul Vund ("Mud Wall") to threaten Tulukhan. Black dragons and bullywug tribes, from the nearby Grel Trumgol swamp, repeatedly attacked the fortress and supply line. These factors caused Thashangriel to abandon the keep around the start of the Second Epoch. Before it was abandoned to nature and beasts, this bastion housed a Thashangriel garrison of nearly 5,000 troops. After they abandoned the place, bullywugs, beasts, and monsters took over.
Over the centuries, the swamp over this ruin has greatly expanded in size, leaving a quarter of the ruins inundated. The massive and eerie fortifications of Glatheon are home to many creatures and are rumored to contain the lairs of several black dragons and their retinue of bullywug minions.