Board Thread:Naruto Discussions/@comment-30168130-20161009021213/@comment-1872728-20161010171442

Ravenlot 27 wrote: If we include Kaguya filler here, then Hagoromo would rather belong to B category since he didn't have an inborn ability to absorb and use nature energy but learned to do it from Gamamaru. To me, it seems that Hagoromo achieved Sage Mode by himself, and he merely had guidance from Gamamaru. I mean, if he learnt it from Gamamaru, wouldn't it make sense for him to have toad markings around his eyes?

I believe that some of Kaguya's descendants have an innate Sage Mode, due to her connection with the Chakra Fruit/God Tree. This Sage Mode can be achieved by themselves, and doesn't have any animal traits.

Hagoromo and Hashirama both demonstrated this with their respective Sage Modes, although Hagoromo's Sage Mode is the counterpart to the Rinnegan while Hashirama's Sage Mode is the counterpart to the Sharingan.