Basically sounds like a legion of Corpsetakers with the added failsafe of a D&D Lich's phylactery.
I like it. Especially the Eight Immortals bit. Although, I'm with earlier posters who recommended they not all be in one place. On top of that, maybe these guys have some beef with the real Dragons like Ferrovax?
And I will say this: Reading this made me think of Shiro's duel and Jet Li's
Fearless, except it'd be body-jumping vampire Jet Li against a Samurai on a mission from Elvis.