The Jade Colossus is possiby my favourite Numenera suppliment. Not only does it provide a fascinating campaign setting including new Foci and organisations, but also includes several other Ruins that you can drop anywhere in the Ninth World for your players to explore. But by far the jewel in the crown has to be the Ruin Engine, with just a few rolls of the dice you can produce a "dungeon" complete with weird installations for your players to explore.