Slaith was once a god who came down to Raktol to conquer the world and spite the gods. His plan did not go according to plan though. A young warrior named Svein the Red smote Slaith with a blade known as Orcaster. Svein opened a portal to Raktol’s bowels, and that is where Slaith has been ever since.
Slaith was once a demi-god, however. He ascended to god-hood by killing his father, Bane. The goblins adopted Slaith as their new god because they saw him as being much more powerful than Bane. But when Svein the Red killed Slaith, the goblins shunned him and began to worship Bane once again. And Slaith was all but forgotten. Few now remember the name, and most only know folk tales about this evil diety, known now as The Darkling. A small group of goblins, however, continued to worship Slaith.
Slaith had two swords, forged by the gods. One of power, forged by Kord. And one of knowledge, forged by Ioun. Neither of the gods knew that Slaith would use these swords for chaotic evil. Nevertheless, Slaith did. In death, Slaith lost his sword of knowledge. It is said, that this sword contains all the knowledge of universe, and with it a mere mortal could rule heaven and earth alike. Slaith was able to keep his sword of power. He now uses it to fight off the hordes of the underworld. Orcaster alone can defeat Slaith, and Slaith’s sword of power is the only one that can break his defenses should he rise up from the underworld.