Question

Question about story quests, I can't seem to unlock leviathan and the thing is I've heard people tell me you talk to Minfilia in Mor Dhona, but the thing is she isn't in Mor Dhona for me, and when I talk to her in the walking sands she has nothing either.

Did you do all story related quests available so far?

Did you beat King Mog? If not the storyline wont open up and she should be in rev toll if you have

If she is still in the waking sands for you, then you're not caught up on the main story

Seems like it. Apparently I have to do Guild Hests =\