Members of the Uchiha clan can generally awaken the Sharingan under two circumstances.
Firstly, if the Uchiha bloodline is pure and strong, such as both parents having awakened the Sharingan, then the probability of their offspring awakening the Sharingan is very high.
However, the awakening of the Sharingan requires emotional stimulation, and even those born into the clan with pure and powerful bloodlines are no exception.
However, as long as their Uchiha bloodline is sufficiently pure and strong, the emotional stimulation needed to finally awaken the Sharingan may only need to be a little.
Secondly: Strong emotional stimulation.
For Uchiha clan members with impure bloodlines, or those whose bloodlines are not strong enough, awakening the Sharingan is extremely difficult. They often need to experience extremely strong emotional stimulation before having a chance to awaken the Sharingan.
It’s worth noting that the so-called pure Uchiha bloodline does not refer to the ordinary sense of ‘pure blood’ between bloodlines, but to the Uchiha clan’s kekkei genkai – the Sharingan itself.
Even the division between the main house and the branch house is not determined by bloodline inheritance where if the parents are from the main house, then the child is also from the main house. Instead, it is determined by who can awaken the clan's kekkei genkai – the Sharingan, to decide who belongs to the main house and who belongs to the branch house.
Therefore, for the Uchiha clan, even if they only have half Uchiha bloodline, meaning only one parent is from the Uchiha clan, as long as they can awaken the kekkei genkai and open the Sharingan, they can still proudly declare: My Uchiha bloodline is incredibly pure.
If they can further evolve the Sharingan to the three-tomoe stage, then they can even declare with pride: My Uchiha bloodline is not only pure but also incredibly powerful.
The reason for this lies in the fact that the awakening of the kekkei genkai itself is a kind of sublimation of one's own bloodline.
Or rather, after awakening the kekkei genkai, the bloodline with the kekkei genkai will engulf and cover the other bloodline, thus completing the purification of one's own bloodline.
However, this is only under the premise that the offspring can open the Sharingan.
In fact, the reason why the Uchiha clan has maintained the practice of marrying within the clan for thousands of years until now is to ensure the purity of the clan’s bloodline.
A half bloodline, marrying with a person from outside the clan, will result in a quarter bloodline for their offspring.
However, a half bloodline, marrying with another member of the clan with a half bloodline, will still result in a half bloodline for their offspring.
If they marry with a 'pure-blood' clan member who has awakened the Sharingan, their offspring's bloodline will be three-quarters.
The more mixed the bloodline, the lower the probability of ultimately awakening the Sharingan.
Even if they can awaken it, the emotional stimulation required will be even more profound.
However, the good part is that once they successfully awaken the Sharingan, regardless of whether their previous bloodline is half, quarter, or even one-eighth, it will directly become 'pure blood'.
When they first awaken the Sharingan, most Uchiha clan members will only have one-tomoe. Only a few will have two-tomoe upon awakening due to extremely profound emotional stimulation or exceptionally pure and powerful bloodlines.
As for the situation of awakening with three-tomoe? In fact, just like the case of being born with the Sharingan, or being born with three-tomoe Sharingan, awakening with three-tomoe has never happened in Uchiha history, except for that legendary ancestor.
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After slowly telling me about the various abilities of the Sharingan and some important related information, especially about the uniqueness of my innate three-tomoe Sharingan, Great-Grandpa finally summarized: "This is the Sharingan, the kekkei genkai of our clan, the reason why our clan has been able to endure for a thousand years and now stands supreme in Konohagakure, recognized as the first ninja clan of Konohagakure."
"And my child, you, who was born with three-tomoe Sharingan, undoubtedly possess the most outstanding talent of our clan at present."
"However, talent needs to be realized into powerful strength through arduous training and continuous learning."
"So, Tsukimi, get ready. Great-Grandpa will be very strict with your ninja training from now on."
The greater the expectations, the higher the demands, and the more effort one needs to put in.
"Yes, I will work hard, Great-Grandpa!"
Tsukimi, who had already closed his Sharingan, opened his black eyes wide, his gaze firm as he assured the old man in a loud voice.
He was a little excited from receiving so much information at once – the abilities of the Sharingan, the bloodline of the Uchiha clan, and the teacher for his future ninja training...
He had too much information to process and needed time to calm down, but he didn't pay much attention to the old man's psychological preparation because he had already prepared himself.
Ever since arriving in this ninja world, Uchiha Tsukimi had been waiting for this day. To cope with future crises and live a better life in the future, he wouldn't waste this heaven-given talent.
Besides, wasn't the old man's strictness and the foreseeable tough training in the future exactly what he had been hoping for? It was his displayed talent that attracted the attention of the clan elders and led to this upcoming special training.
Otherwise, how many ordinary clan members would get such an opportunity? Especially a one-on-one lesson from Uchiha Hiken, the former clan elder.
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