Board Thread:Theories and Speculation/@comment-45444155-20200806213256/@comment-45903789-20200808132647

Jira89 wrote: I thought we had written enough about it. Orochimaru doesn't have any Senjutsu. I recommend you to read official translations, not the fan ones.

In chapter 648, Orochimaru don't say "Curse Mark is Senjutsu chakra" but "Senjutsu power is the source of curse mark". A little bit different, the power of Senjutsu is the Nature energy, Orochimaru just want to point this. And then he say "i suppose you could call it senjutsu susano". He use the terms like "suppose, you could" because Juugo doesn't have a real Sage technique, he is not a Sage, he use nature energy roughly.

ReweR 1331 wrote: Yes, but where can we find this moment of learning how to enter Sage Mode based on the existing chakra senjutsu? Naruto immediately entered Sage Mode as soon as he formed the chakra senjutsu. This is perhaps too much digging. Sage modes feature specific workouts and places where they can be learned. Somehow users assume the appearance of creatures or aspects of those areas for unspecified reasons.

Senjutsu power is senjutsu chakra. How the curse mark works, for both of its versions, are secret. I "suppose" you can call it a "hidden technique." But one thing it is certain is that it uses senjutsu power/chakra.

Chapter 579, Kabuto says that Jugo's body passively absorb nature energy. Combined with his chakra, that is literally senjutsu chakra.

The difference with Sage mode and curse marks are probably the balance with nature chakra/energy. If not, then the difference is the nature of one's own chakra, whether it is evil or not. It is just my assumption but like I said it is a "hiden technique."