Genghis_Sean
High School English teacher
I must be an idiot. It took me probably a dozen games before I figured out that when you clear a Hydrocoral Brain, or whatever, it lights up. Therefore, you can scan the map and look for unlit ones to see which ones you've missed. Maybe everyone already knew this, but I just figured it out. It would have saved me a lot of trouble had I known it earlier. Thought I'd make a post in case anybody else was similarly clueless.