Here's a few hints for three more, not yet announced.

One has worked with dead men. One was not sacrificed by his father to a jealous god. One has worked with chemicals. One knew Dumbledore. One has worked with fairies. One is just a number, not a free man. One is a town in Nassau. One will wear sable. One will wear a birthday suit. One knows what lies between the pit of man's fears and the summit of his knowledge. One has a small part. One has a SMALL part. One you're never going ...