Oh no. Vampire hierarchy is very simplistic and brutal: they only bow to another when they've been thoroughly beaten by said being (as in almost killed). Only the strongest can claim the title Master Vampire.
Thus, Mortis is by far, far, far the most powerful vampire. Razvan is special because he mimics Mortis's powers to some extent and then uses his own as a sort of... amplifier I guess. You'll see later. ^_^
And this is more my style.
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"You misunderstand, Jedi," Riordan corrects him. "Yes, the life can be ripped from their bodies and they die just as any other being but the only way to truly kill them is to burn the heart. However, even then they possess incredible capabilities we will never be able to grasp completely."
Shouten Yaiba hums low through the Force, the sound much like a slow beating heart. Black smoke swirls around the sword's grip and Riordan subconsciously pulls his hand from his robes, shaking it so that the smoke disperses. George barely catches the faint and eerie whispers he believes is emitted by the weapon itself. "Ashes rise now and become my shield... flames burn now and become my blade..."
Riordan looks down at his hand briefly, as if studying it. "Their bodies can regenerate at immense speeds. Not only that but if Mortis's age is anything to go by then feeding off other living organisms replenishes their own life or can even be used to heal wounds. They are ageless. Immortal."
"Long ago... they used to be plentiful. Thousands of them spread across the universe. The Elders and others banned together to cleanse life of the 'dark taint' it had allowed to emerge. After all, it is the evil within men's souls which gives birth to these cursed creatures," he adds, shame buried somewhere within his voice.
"They created something... I... I'm not sure I understand how or even what it was exactly. The vampires numbers rapidly diminished into a mere dozen; the entire species on the very verge of extinction. But in the end, victory was stolen from the Elders and their allies and the glory they had known... came at a grave cost. Mortis eradicated their entire civilizations like they were nothing...."
A pause. Reflection. "All that was left of once great empires is but what remains today: buried secrets and rubble." He sighs. "If there is any power which can be used against one of the vampire blood... then it lies in an Elder tomb. Perhaps the very one which you saw in your vision, Jedi."
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Okay, I realize this may get confusing (cause I even get lost from time to time), Shouten Yaiba is now in what is referred to as his 'sealed' state. The blade has 'shattered' and now only the handle remains. This is what Riordan is holding just on the inside of his robes.
There is a slit inside the fold of Riordan's robes where the handle usually rests, allowing easy access or (as you see here) him to use it to merely keep Shouten close at hand. Shouten acts to comfort and calm Riordan in many situations much as a Jedi's lightsaber does the same.