Star Wars: Knights of the Old Republic II: The Sith Lords is the sequel to Star Wars: Knights of the Old Republic. It was developed by Obsidian and published by Lucas Arts. According to the game's producers, the change of developers was primarily due to BioWare's occupation with other titles, such as Jade Empire and Dragon Age. BioWare is understood to have recommended Obsidian Entertainment as an alternative developer, having worked with many of Obsidian's key members when they were part of the now-defunct Black Isle Studios. The Sith Lords was constructed using an updated version of the original Knights of the Old Republic Odyssey engine, which Obsidian obtained from BioWare.