Is it entirely necessary to get an S-rank in every mission of normal mode in order to get an overall S-ranking for the campaign? If so, does anyone have any idea how to get an S-rank for mission 22 (Crystal Calamity)? I have tried every combination of CO's and strategy I could find in the FAQs and the best I can seem to do is B-rank! I get a score of 100 in all areas except 'power'. What is your 'power' score a reflection of? Thanks to anyone who replies... This game is so addictive and challenging!