Quote Originally Posted by David75 View Post
http://en.wikipedia.org/wiki/Bluebeard
Might help understanding.
I guess Caster did tell that name as it was the nearest example of his appearance on earth, or the being nearer to his state of mind
Kind of disappointing how i never heard of him, though i guess that's what you can expect from a shitty summoner like Killy Mckill or whatever his name is.

Quote Originally Posted by Buffalobiian View Post
One thing that's been revealed in FZ that wasn't apparent in FSN was that one can choose the attribute that you want your servant to be classed in. How that works with the "one servant per class" I have no idea - perhaps first-in, first-serve?

It does hint at why Rin's servant was an Archer class despite his main fighting style being so un-archer-like. The catalyst determines the hero. The incantation add-on (if any) determines the class (if it can be applied to the hero). I just can't remember if Tokiomi specifically requested an Archer class.
You can't, not for certain anyway. What you can do is make an educated guess since you'll be aiming to summon particular characters and should already know what roles they would fit the better, but it's quite possible they could fit some other role as well. Emiya and Hercules could have easily had been a saber, just how Gilgamesh could have probably rolled any other knight class as well.