User blog comment:FairyRaven/Fairy Tail Chapter 392: You Must Not Forget, Review and Commentary/@comment-7418318-20140711144204/@comment-7418318-20140712130353

I have two rather unlikely possibilities in mind.

The Faces look a bit like antennae and they are charged with super-dense ethernano.

Maybe if "shoots" a telepathic message at one of the Faces, it will resonate with it and spread from one Face to the next and anyone close enough to one can pick up the message.

Or alternatively getting surrounded by the ethernano-rich air could give him a temporary power and thus range boost.

Especially the latter seems unlikely in the extreme to me, since Wendy was only able to make use of the ethernano in the air due to being able to eat air. Warren can't do that.