Shade
Monster Junkie
That seems quite appropriate. Updated.
So...
"Crystal skeletons cannot speak, but understand the languages of their creator and any languages they spoke in life. Additionally, crystal skeletons may communicate telepathically with any other crystal skeletons with x feet."
Crystal skeletons understand the language of their creator as well as the native tongue they spoke when they were alive. They communicate with their creator with nods or shakes of their head and share a telepathic bond with others of their kind. There is no record of crystal skeletons communicating with others, though it is thought possible.
So...
"Crystal skeletons cannot speak, but understand the languages of their creator and any languages they spoke in life. Additionally, crystal skeletons may communicate telepathically with any other crystal skeletons with x feet."