Bully Creek Thundereggs

Far away from anywhere, somewhere in the mountains 45 miles or so north east from Secret Ridge, is Bully Creek. I Haven't heard much about this location - save that it is only accessible on foot, meaning that these eggs must be dragged back to civilization in your backpack. The characteristic - of the ones I have seen anyway - is a yellow-greenish opal filling that is quite unlike anything I have seen elsewhere.