Mangekyō Sharingan abilities came in all kinds, and quite a few were downright broken.
Take Kamui, the ability of a certain wicked little Uchiha. For ninja without Space-Time Ninjutsu, it was nearly impossible to counter.
Well, the key was having both Mangekyō Sharingan working together.
Obito Uchiha's Kamui had a five-minute limit. If an enemy kept attacking without pause, Obito would have to resort to something else, such as Izanagi, to avoid taking damage.
But if Obito had both Mangekyō Sharingan, things would be different.
Even Minato Namikaze during the Nine-Tails' Attack might not have been a match for him.
The Mangekyō Sharingan was strongest when both eyes were together.
This was not about Susanoo. It was about pairing the abilities of both eyes, like Sasuke Uchiha's Amaterasu and Kagutsuchi. Without Kagutsuchi, Amaterasu would lose much of its power and control.
And without Amaterasu, Kagutsuchi...
It seemed pretty useless.
Of course, with Kagutsuchi, there was no end to what one could do with Amaterasu.
When it came to using Amaterasu and Kagutsuchi, Sasuke might not even measure up to Uchiha Hikari before him. This Uchiha Great-Grandmother had truly mastered Kagutsuchi.
Uchiha Yi was curious to see just how far Hikari could go.
Soon, Yi felt Hikari place a mark on his hand. In an instant, he understood how her ability worked.
"That really is an impressive ability," Yi said, unable to hide his admiration. If Hikari could be nurtured, she might one day grow strong enough to stand against the Ōtsutsuki Clan and become a mainstay in the fight against them.
Yi also had a theory. Hikari might have awakened her Mangekyō Sharingan in a battle against the Senju Clan or the Uzumaki Clan. She had used Yachihoko on them and drained their chakra.
That would explain why her Mangekyō