Have fun because after playing FFX twice i gave up on trying to get the ultimate wepons because it's either real easy to get the cerst but then the segil is a MF or the other way around. Like for Tidus i think his crest is around the beach where you meet waka and after a certain event you cant get it again, and Lulu you have to dodge 100 lightning bolts in a row to get her segil or something, my advice is to custom make your own "Ultimate Wepon"