I think it depends on what area you are in, as to what "new" stuff you will see. Anything "new" will likely look familiar though, and just be a variation of something you have seen before (like the Elementals you can encounter in AP).As to the Quetzocaotal, I think it is a variation of the flying snakes ... not sure if it was one of those things that are in the game physically, but never show up (unimplemented feature)?
Tools for Wizardry(r) 7