Guild Member Grey:
You must gather 20 light-blue runestones. These runestones are obtained by destroying manashen gargoyles or enchanted stone golems in the area near the Ivory Tower. To protect their precious tower from interlopers, the mages apparently have inplanted runestones in the creatures of that area and are controlling them.
This is all I will say on this matter. If you are a true hunter, you must gather the information and find the items yourself. Don't expect any more hints!
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