Gyo

Gyo (凝, Gyo) is an advance Nen Techinique.

Description
Gyo (凝, Focus) is an advanced application of Ren by which a Nen-user concentrates a larger than normal portion of their aura into one specific body part. Gyo increases the strength of that one body part, but leaves the rest of the body more vulnerable. Gyo is most often used in the eyes, allowing a Nen-user to see aura and things which would otherwise be hidden (e.g. Nen objects hidden by In).