Karrossi

The Karrossi were the followers of the  Karros, also known as the Lord of Lore, who was arguably the greatest Sith philosopher of his time.

Rather than take an apprentice, as per the usual traditions of the Sith order, Lord Karros instead cultivated a band of philosophically-minded followers with whom he endlessly debated on all manner of subjects related to the study of the Force. Following his death, his followers named themselves "the Karrossi" in honor of their master, and erected a massive mausoleum on his homeworld of, wherein they lay his remains and greatest writings.

The Karrossi continued their master's studies into the nature of the Force after his death, though the cult, such as it was, eventually died out and ceased to exist sometime prior to the, when the Jedi known as the Apostate entered the tomb and learned of the ancient cult's existence from the undead of Lord Karros.