Board Thread:Theories and Speculation/@comment-1872728-20200725151448/@comment-46279039-20200729213756

They say that but is a surrogate. Juugo don't use any technque, is not a Sage. He naturally absorb some nature energy automatically and mostly uncontrolled. Orochimaru, Sasuke, Anko are not Sages.

You have to weigh and evaluate all the statements said in the manga. I remember a part when Juugo said that someone called his form "sage mode", but who is that someone is unknown. juugo does not use Sage Mode...