[theory]
Based on Kaguya's reaction, Amaterasu might have been Indra's dojutsu and/or she may have seen it before
Ashura had Doton, Suiton, Yang affinity and produced Mokuton while Indra had Raiton, Katon, Yin affinity and was able to use Enton. The elements are perfect opposites but Sasuke doesn't actually combine his affinities to make a KKG like Hashi would.
The flame ignites when the eye has its target marked, but from what I understand it doesn't actually ignite but rather gets summoned instead, because the users were never said to combine their nature affinities.
So where does Amaterasu come from considering Mokuton originates from the Juubi's body and Sharingan from its eye ?
I think what the Mangekyo does is summon the flame from a different world/dimension as Obito proved that dimensions can be linked with dojutsu. The ability to summon the flame would basically derive from Kaguya's ability to summon dimensions which I will elaborate on.
BZ described Amaterasu as a "fire from Hell".
The statement caught my attention because one of the Rinnegan's summons is the King of Hell. Nagato named the Path 'Naraka' which happens to be the Sanskrit word for 'Underworld', a term used to describe 'Hell' in Christian religion
However, the 'Underworld' is also known as the "Pure World" in NV because that's where the dead go regardless of whether they're good or bad, coincidentally, the King of Hell grants Outer Path the ability to summon souls from the "Pure World"
Hagoromo's ability to summon souls from the after life suggests that he may have been linked with the Pure World in the same manner Kaguya was linked to her dimensions, it also suggests that Kaguya may have been linked to it as well since she was the Juubi.
The 9 tomoe on the JuubiJin's back could be said to represent 9 dimensions linked to Kaguya's eye however, we've only seen 6 of them so far. It's likely that the Pure World is one of the remaining 3 dimensions we haven't seen hence why Hago's dojutsu has control over it.
Indra's jutsu might have derived from Kaguya's ability to shift spaces, along with his father's control over the King of Hell and his JuubiJin predecessors having their dojutsu linked with the realm of the dead.
The flame is said to represent a "Material World of Light" which sounds like an accurate description of the after life. I think what MS does is "shift" the flames from the Pure World, similar to how Kaguya would for example shift a portion of Lava from her dimension instead of a whole ocean.
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Ashura had Doton, Suiton, Yang affinity and produced Mokuton while Indra had Raiton, Katon, Yin affinity and was able to use Enton. The elements are perfect opposites but Sasuke doesn't actually combine his affinities to make a KKG like Hashi would.
The flame ignites when the eye has its target marked, but from what I understand it doesn't actually ignite but rather gets summoned instead, because the users were never said to combine their nature affinities.
You must be registered for see images
So where does Amaterasu come from considering Mokuton originates from the Juubi's body and Sharingan from its eye ?
I think what the Mangekyo does is summon the flame from a different world/dimension as Obito proved that dimensions can be linked with dojutsu. The ability to summon the flame would basically derive from Kaguya's ability to summon dimensions which I will elaborate on.
You must be registered for see images
BZ described Amaterasu as a "fire from Hell".
You must be registered for see images
The statement caught my attention because one of the Rinnegan's summons is the King of Hell. Nagato named the Path 'Naraka' which happens to be the Sanskrit word for 'Underworld', a term used to describe 'Hell' in Christian religion
You must be registered for see images
However, the 'Underworld' is also known as the "Pure World" in NV because that's where the dead go regardless of whether they're good or bad, coincidentally, the King of Hell grants Outer Path the ability to summon souls from the "Pure World"
You must be registered for see images
Hagoromo's ability to summon souls from the after life suggests that he may have been linked with the Pure World in the same manner Kaguya was linked to her dimensions, it also suggests that Kaguya may have been linked to it as well since she was the Juubi.
The 9 tomoe on the JuubiJin's back could be said to represent 9 dimensions linked to Kaguya's eye however, we've only seen 6 of them so far. It's likely that the Pure World is one of the remaining 3 dimensions we haven't seen hence why Hago's dojutsu has control over it.
You must be registered for see images
Indra's jutsu might have derived from Kaguya's ability to shift spaces, along with his father's control over the King of Hell and his JuubiJin predecessors having their dojutsu linked with the realm of the dead.
The flame is said to represent a "Material World of Light" which sounds like an accurate description of the after life. I think what MS does is "shift" the flames from the Pure World, similar to how Kaguya would for example shift a portion of Lava from her dimension instead of a whole ocean.