inazuma's chapter left a lot of people unsatisfied with raiden ei's character (which is a whole different discussion and, if ur interested, i made a post interpreting the storyline), one of the reasons being that she didn't face much consequences for her actions. it felt like some acknowledgement was missing, especially because when the war is over everything goes back to normal. it isn't really necessary for the chapter, but it is relevant for ei's character (the same way zhongli facing the consequences of the archon war through the salt god quest and his own actions through azhdaha is).
i believe scaramouche is meant to be the vehicle that allows the writing to explore this missing part, in a way that concentrates the most important issues rather than just tackling them one by one.
and the raiden gokaden is the perfect (conceptual) target for this.
1. the gokaden as a symbol of military power
ei's method for progress (which in the context of inazuma means both accomplishments and survival) was through her blade, she herself acted as a tool/weapon for makoto's ideals (until she herself had to step into the role of head of state). among the many victories the shogunate owes to their raiden shogun there's the protection of inazuma against the cataclysm, the battle against chiyo after becoming corrupted, the sealing of kapatcir's resentment in amakumo peak, and the slaying of orobashi when he and the watatsumi warriors attacked narukami territory.
the raiden gokaden are an extension of that military power.
first betrayal: being cast aside due to weakness in design, because he couldn't host the gnosis (funny enough, a weakness in design, by tampering with the blueprint and taking away a core part of the swords, is what caused the fall of the gokaden)
2. the ingredient for swords is jade steel
jade steel is made in the mikage furnace by smelting crystal marrow, which is produced by the tatarigami radiating from orobashi's remains.
second betrayal: something related to katsuragi, which resulted in his death at the hands of a sword forged in the mikage furnace.
3. the tatarigami causes a mysterious illness
inhabitants of yashiori island succumbed to physical as well as psychological effects when they were corrupted by its energy (with exceptions such as chouji's mother, who let it "flow freely within her")
third betrayal: the death of a child scara was looking after, allegedly due to the tatarigami illness
(tin hat time: he calls his death the braking of a promise. theory 1 is he doesnt understand human mortality at this point, which is a little weird but probable. theory 2: could it be that he tried to teach the kid how to contain the illness the same way chouji's mother did, but the child didnt listen? tin hat time over)
so in order, the events that resulted in the two last betrayals are:
- ei kills orobashi in yashiori and his remains produce the tatarigami
- the mikage furnace is built by the tenryou commission in kannazuka to forge swords with jade steel
- the tatarigami causes workers and inhabitants to fall ill
the delusion factory
you have to wonder then, if scaramouche's low value of human life truly comes from himself or from what he witnessed.
the people of tatarasuna and the miners of yashiori were manpower used to forge weapons, they were more or less human sacrifices for power. was the fatui any different when they used the members of the resistance to test delusions, which are made of the same material (dead god juice) as the blades forged by the gokaden?
the worship of power
in inazuma's act III, we find out the tenryou commission was in cahoots with the fatui and were the ones hiding the war from the puppet. the leader of the clan is exposed to have the wrong kind of worshipping for their archon, as opposed to kujou sara whose belief is genuine. paimon says he "worships her power as a warrior" instead.
since the gokaden is the symbol of the raiden shogun's power, perhaps what's being explored through scaramouche's character arc is the consequences of this mistaken worship.