Talk:Expedition/@comment-97.90.135.175-20150126161304

How does unlocking expeditions work? I thought they unlocked in order (i.e., finishing 1 unlocks 2, then 3....) unless posted above. I just finished 17 and it unlocked 21 instead of 18? Is that normal and how do I unlock 18? If it helps, I'm just trying to finish requirements to get the Z1 quest.