Liliana Vess Defiant Necromancer

"Oh, well," said Gladio, snorting a bit, and then there seemed to be a sort of shift in the air, as if Liliana had gone and flipped a sort of switch, a switch that activated his...oh no...nerd mode, "Leviathan has always disliked humanity, so it wouldn't be surprising that she just didn't want to lend us her powers; she definitely wasn't happy about it when we woke her up so that Noct and Lunafreya could commune with her, but I might be a little irritated if a bunch of ants tried to rouse me up from a 2000 year nap, too. And the power of the crystals is extracted by the royal family itself; they're usually found around Havens, and so Noct could just...pull their energy and use it. There are some more industrial ways of extracting it, but the magic's never as powerful when you do it that way. As for how they're created and why they're tied in with the bloodline? That is all Bahamut. He's the one who created the crystals to help combat the Starscourge, which....well, there's not a lot known about the origins of the Starscourge, but some sources say that it arrived with the gods, on the Meteor of the Six, which crashed into Eos before the dawn of civiliza--"

He stopped, abruptly, as he realized he was sort of rambling and shook his head. "Oh, man," he said, "you probably better not get me started, I'm gonna end up talking your ear off all night..."