Netsugan

The Netsugan (熱眼, Heat Eye) is a which manifests exclusively within members of the Hanamura Clan. It is an exceptionally rare which has only appeared in a handful of the Clan's members over the course of its many generations of existence.

Overview
As a whole, the Netsugan is incredibly unique in terms of the ability it bestows upon its wielders. Unlike the entirety of other bloodline limits classified under the title dōjutsu, the Netsugan does not grant those whom wield it the capacity to perceive chakra, or its flow, in any way. However, it does permit its wielders the ability to access a form of "thermal vision", in which the user may perceive all objects in a number of colors based upon their temperature. Objects that are cooler tend to appear various shades of blue, with the darkest hue denoting freezing temperatures. On the other hand, objects that are warmer tend to appear various shades of red. The highest of temperatures, such as the certain ninjutsu, appear white, whereas the rest appear as shades of progressively darkening red. Furthermore, another major difference between the Netsugan and typical dōjutsu is the fact that the user can choose whether or not to manifest both eyes, the right, or the left at any given time.