Unfortunately no, because you can't pay life you don't have, even if you wouldn't lose because of it. :P If I'm at 1, I can't cast Apostle's Blessing by paying the Phyrexian white cost, for example. However, life loss isn't damage, so I can cast Spoils of the Vault and go to a negative life total for a card if I have the Phyrexian Unlife out.

Okay so if the life lost is part of the casting cost then you can't do that. but if it is just a negative side effect of the spell then you can do that. So you can put yourself past 0 with Read the Bones?

Yep, you sure can :) Though this deck doesn't really need it with the amount of cards you can dig through with Spoils of the Vault and Plunge into Darkness.

wow this is an awesome idea plus +1 c:

Haha well thank you :)

have you thought about Platinum Angel?

Gods Willing>Apostle's Blessing?

Platinum Angel is a ridiculously high drop for this deck to pull off, and it dies really easy. :P

I like Gods Willing, but Apostle's Blessing serves a dual purpose in this deck. One, it's one of the only protection spells that can give protection from artifacts, and two, the Phyrexian mana can lower my life total and buff the Shadow by paying the life.