I stand corrected. I don't see the X in
Polyxena as being an X in the middle of a name, as I am seeing the name as its two components, Poly and
Xena. I understand the sound of the X in
Alexander and
Nyx, but all the pronunciation guides I've seen say that, when X begins a word, pronunciation is Z (Except in Chinese).
So, X is the same in
Xanthippe,
Alexander, Xenophone, and
Polyxena? OK.
PS:
Come to think of it, the Russians spell
Xenia K-S-E-N-I-A.