Board Thread:Theories and Speculation/@comment-25283946-20150203145352/@comment-1512913-20150203221448

Obito simply used Kamui to distort Katon. What I meant by Katon used through Sharingan is using Sharingan chakra and changing its nature into Katon.

Also for all the "black lightning is lightning+yin" supporters, unfortunately for you, nope. Neither 3rd Raikage or Darui can use Yin Release.