Board Thread:Theories and Speculation/@comment-35051547-20180320000346

I believe Hashirama learnt his sage mode at shikkotsu forest and this he is a slug sage. Some people believe you have to be a sage to summon an animal which resides in one of the sage regions and that is not true. An example being Sasuke who can summon Aoda. Sage mode is a technique that can’t be self taught as human generally can’t even sense nature energy let alone control. Just look at the oil waterfall in Mount myoboku which allows you sense nature energy more easily. The fact that hashirama had large chakra reserves doesn’t mean he could learn it by himself, even Hagoromo needed the help of Gamamaro to master sage chakra. So the only reasonable explanation is that Hashirama is a slug sage who learnt sage mode at the Shikkotsu forest. Look at the connections; he is able to heal himself without weaving seals(an ability Katsuyu), his clan is also known as the Senju clan of the forest, and if you look at it that may also be where he mastered wood release. Naruto learnt the Rasenshuriken but it was with sage chakra with which he was able to stop it from also causing harm to him. Orochimaru’s tests with Hashirama’s DNA on children always resulted in failure because only a handful of people can handle nature energy,even with his cells on Madara’s body they were still absorbing nature energy. I don’t think Hashirama was the only person to try and learn sage mode at the shikkotsu wood but was one of the few perhaps only one who succeeded, maybe even tsunade and Tobirama tried but because the couldn’t enter sage mode they worked on other ninjutsu. 