Bring the 'foundation' (I forgot where to find it) to Jibudu in Muska Rakka. Then he will give you an 'ancient dolly'. Take the dolly to Marnia in Yellow Drops and then you will receive the sun gem! It has special powers: +3 all creatures, +10 attack power and +10 all elements. This is very usefull if you are planning to build-up very quickly.