Vagabonds of Lothilia
One of the most impressive complexes in all of Lothilia, the Astral Mountain was built not to repel invaders, but to keep them in. At the highest peak of the Astral Mountain lies the World Gate, a massive artifact that can open portals into the multiverse. It is also one of the locations a traveller from the multiverse might come in. While certain individuals are welcome, such as the Shardmind Githzerai, it can be a hole from the Infernal Hells were demons can invade. Also, the growing extradimensional threat known as the King of Many Stars continues to grow.
While it was originally a fortress, built by Deva towards the end of the previous age, it has since grown into more. The Deva, being both wise and possessing knowledge from multiple life times, turned their mountain into a fountain of knowledge. The Astral Mountain contains some of the most complete libraries in the world, museums full of ancient artifacts, both mundane and magical, and schools dedicated to magic, philosophy, war, psionics and more.
As of recently, it has also become a place of sanctuary for thousands trying to escape the war. The Deva welcome peasant and noble, farmer and soldier, no matter what faction, and offer them the quiet, safe life as disciples, monks or even guardians of the world gate.
The Astral Mountain has long earned the ire of Lothilia by refusing to take part in the empire or for hiding criminals who pproach them. However, it is also universally agreed upon that the Astral Mountain is unsiegable and no army sent to bring the Deva to heel would be able to survive the harsh mountains, freezing weather, steep climb or high altitudes, all before starting the actual sieging process. The trip is dangerous enough for pilgrims. An army would have great difficulty.