What the title says:
A lot of people on NB seem to think that Sage Mode is run on purely Nature Energy meaning the Sage Mode users have infinite chakra/stamina while in Sage Mode (which by going by this theory would mean they would never go out of Sage Mode). That is wrong. Sage Mode is made up of a perfect balance between Physical Energy, Spiritual/Mental Energy and Nature Energy. That's why all Sage Mode users have been good at chakra control: Hashi and Kabuto could use medical ninjutsu, Minato, Jiraiya and Naruto are Rasengan users and Madara has perfected his Susano. This means that once a Sage Mode user runs out of a. Physical Energy or b. Mental Energy they can no longer use Sage Mode or they suffer the transformation issue. This also means that Senjutsu is not purely Nature Energy so things like Tayuya's ghosts (which steal Mental/Spiritual Energy) render it useless (so long as the ghosts can touch the Sage Mode user or his/her jutsu).
TL;DR: Sage Mode is not infinite because it is the result of combining normal chakra with nature energy.
Hope this helps!
A lot of people on NB seem to think that Sage Mode is run on purely Nature Energy meaning the Sage Mode users have infinite chakra/stamina while in Sage Mode (which by going by this theory would mean they would never go out of Sage Mode). That is wrong. Sage Mode is made up of a perfect balance between Physical Energy, Spiritual/Mental Energy and Nature Energy. That's why all Sage Mode users have been good at chakra control: Hashi and Kabuto could use medical ninjutsu, Minato, Jiraiya and Naruto are Rasengan users and Madara has perfected his Susano. This means that once a Sage Mode user runs out of a. Physical Energy or b. Mental Energy they can no longer use Sage Mode or they suffer the transformation issue. This also means that Senjutsu is not purely Nature Energy so things like Tayuya's ghosts (which steal Mental/Spiritual Energy) render it useless (so long as the ghosts can touch the Sage Mode user or his/her jutsu).
TL;DR: Sage Mode is not infinite because it is the result of combining normal chakra with nature energy.
Hope this helps!

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