This is one of those cases where there are two hostas with the same name. One is registered and, therefore, the "official" version of H. 'Phantom' while the other is a non-registered plant and needs to be renamed to avoid further confusion.
 

This is a seedling of H. 'Riptide' which was registered jointly by Bob Solberg of Green Hill Farm in North Carolina and Dr. Jim and Jill Wilkins of Michigan in 1995. It is a heavily rippled, large size (22 inches high) plant with light purple petioles. Pale purple flowers bloom from late July into August but do not set viable seeds.

The New Encyclopedia of Hostas by Diana Grenfell (2009) states: "Ghostly, grey-coated leaves, intensely red-dotted and backed petioles, and thickly glaucous scapes make this an extremely garden-worthy hosta."

Similar plants include H. pycnophylla.

Hosta Helper will call this plant 'Phantom' (Solberg)

This cultivar was listed on the MyHostas Database website. Originated by Klaus Jentsch of Staudengärtnerei (Perennial Nursery) Jentsch in Germany, this non-registered cultivar is of unidentified parentage. We have seen this one listed as H. 'DD Phantom'.

Hosta Helper will call this plant 'Phantom' (Jentsch)