Do any of the published books contain more information than in Book 2 concerning the surface of Drinax, such as a map, more data on the Vespexers, etc? I threw a one-off encounter at them down there that has led them to believe a foreign power is deliberately supplying raiders and causing chaos downstairs on Drinax, and I subscribe to the "sure why not" school of GMing. Now it may be a major plot arc tracking this down, and I'd like to know if there's anything Mongoose-official before I go and put all the work in myself.
