This game is really fun but im having trouble killing Gustco (Gutsco?) I have all White Mages at lvl 15-16. My current stradegy is two of them cure whole party while other two ice staff him. Not working. Does mini/toad work on him?

With the second crystal I wanna become all geomancers xD lol I wanan try and keep going with a caster team but scholar can only use 1-3 levels so I want geomancers, but I dont even know if they can use magic! lol What levels can they use? Can they use White, Black or both? Whats this 'randomly draws powers from nature' thing? Can someone explain that?

I also wany to try ranger since I love bow and arrows and they have cool elemental arrows BUT im scared of wasting too much money on arrows since you'll need alot.