I was hoping to get 2 Master Spheres from Dark Ixion. I understand from this site that the first form of Dark Ixion does in fact drop Master Spheres one-eighth of the time.

Is it possible that I could get a second on that? I've just defeated Dark Ixion my eighth time and still no Master Sphere :( I'm pressing on, but I'd like to know that I'm not doing this in vain.