Board Thread:Naruto: The Last Discussion/@comment-732150-20150205151208/@comment-24593592-20150210091930

Elveonora wrote: I presume they had the Byakugan in the "deactivated" form, without the veins and all. Then chakra came along and boom, their eyes could suddenly zoom and see through shit.

My guess is that they could use the Byakugan for X-Ray and 380 degree vison. The fruit cause them to see chakra systems.