Silver blood

All creatures with silver blood have increased healing abilities. As silver blood is laced what natural chemicals and hormones that stimulate the body in such a way that it will heal much faster and with far less pain then in red or black blooded species.

However these chemicals have proven to be extremely toxic even lethal to red and black flooded species. Only the angels, the youngest of all silver blooded species, have a genetic makeup close enough to those of red and black blood that their blood will not poison but will heal any wound it comes into contact with and if consumed has been known to extend or prolong the lifespan of ohers.