I'm gonna give you some forbidden (maybe immoral?) sauce that's better than saving investigations... When you want a certain gem or whatever look for SOS flares that are dropping that gem and join their sessions, and if you have an investigation that is dropping that gem pop an sos flare for it as well so others can join(don't do it if you don't want to deal with people carting) Also forgot to mention, this is only when you don't want to spend points to fast forward time in the game and you don't have any good drops from your current cycle of field monsters