Would Xykon become a demilich?

[137beth]

No, for two obvious reasons:

--while it is not listed as a limitation on the template, demiliches do not talk. Can you imagine Xykon voluntarily assuming a form where he would never speak again?

Wait, what? I've never heard that. In fact, the rules explicitly contradict this statement:

Demiliches speak the languages they knew as liches and as living creatures.