En.Lil and his men had implants for telepathic communication. The technology is nearly at hand. In Resurrection and Redemptions (books 3 and 4 of The Alterran Legacy Series), the implants cause En.Lil's abilities to evolve.
Telepathic Communication Has Become a Reality
How many times we wished to be able to contact someone without words… New company for scientific and military research plans to make the dream come true by giving us a possibility to send text or audio messages by thought. The technology of so-called synthetic telepathy...