Will of The Mark
Khyber shards are found beneath the earth near layers of magma or sulfur vents, typically growing on volcanic cavern walls. They are found throughout Eberron but are particularly common in areas known for fiendish activity, such as the Demon Wastes. Khyber shards have a smoky appearance, with writhing midnight blue to oily black veins running through them. They are sometimes known as nightshards or demonstones. Khyber shard items have an affinity for binding magic. They are common components of binding diagrams, soul trapping spells and similar magic associated with binding creatures.
Khyber is also said to be the body of one of the three Progenitor Dragons that created the world of Eberron. It is a massive subterranean realm that is filled with Devils, Deemons, Daelkyr, nightmarish, and the sleeping Rajah that were bound by the Dragons and the Gatekeepers.
One of the regions of Khyber is the Vault of the Keeper where souls taken by Keeper’s Fangs are delivered. There, an ancient Draconic Lich claiming to be the Keeper lords over them and inflicts hellish suffering upon them.