Magnitude10 - Profile

Nue seems to not be based on one of the treasures.

The dogs take one slot.

The Six Eyes was the only thing that was 1 at a time.

Naobito and his son, Naoya, both had projection sorcery.

I’ll cast a vote against only one Ten Shadows user being able to exist at a time. It only makes sense for the 10S to be that exclusive if it’s literally summoning a group of beings that actually exist in the world. But that just sounds like weird head-cannon to me. Cursed techniques in JJK allow their wielders to create phenomena based on stories, ideas, etc., that actually exist in universe, I.e., Achilles paradox (Limitless,) animation frames (Projection Sorcery,) and voodoo (Straw-doll.) While the 10S is an exceptionally sophisticated and high level technique, in the end, it’s just a CT based on the Ten Sacred Treasures. The Shikigami it creates are most likely borne from the technique itself, rather than a pre-existing shadow realm. The death and totality mechanics are also just the function of the CT’s internal logic, otherwise each new user would come with a bunch of dead shikigami. With regards to how it functions in this story, I would imagine that when someone is born with the Kekkai Genkai, the shikigami are born in and summoned from their innate domain. Of course, it’d be pretty scary to have a clan full of Mahoraga suicide bombers. But I imagine 10S would be a pain to breed for. Honestly, I (and the Nara clan,) would just be disappointed if none of Akira’s kids had it.

It’s good that, when Excaliburs details get leaked, he can say it chose him for his unnaturally high aura capacity, (and also that it’s forcing him into this nonsense.)

Hand over the next chapter

Just look at the auxiliary chapter for Gojo’s scaling.