How Did Itachi Uchiha Awaken His Mangekyou Sharingan?
The Mangekyou Sharingan, an upgraded form of the Uchiha Clan's Dojutsu Kekkei Genkai, Sharingan! It is one of the most sought after eye-technique. But due to its rareness, only a few was able to unlock it. So how did Itachi Uchiha Awaken his Mangekyou Sharingan?
Most Uchiha's misunderstood the requirements needed to activate Mangekyou Sharingan. It is initially awakened by the trauma suffered from witnessing the death of someone close, and was greatly misconceived that one needed to be the person responsible for the death, which developed into an Uchiha, killing someone they are close to, for the sake of power.
"Itachi Uchiha awakened his Mangekyou Sharingan at the age of 13, after witnessing his best friend, Shisui Uchiha's suicide. This was due to Danzo Shimura wanting to take both Shisui's eyes. This event happened shortly before the Uchiha Clan massacre."
How Strong Is Itachi Uchiha's Mangekyou Sharingan?
The Mangekyou Sharingan abilities differ greatly depending on the user but are similar in nature. It grants powerful abilities on both eyes and a handful of new Jutsu that is awakened with it. Here are the examples of our mighty shinobi's techniques and usage of his abilities.
Itachi's Left Mangekyou Sharingan Dojutsu
Itachi Uchiha awakened Tsukuyomi on his left eye; it is a frightening Genjutsu that ensnares an individual just by making eye-contact with the person and traps them in a world he created, altering one's perception of time. Itachi uses this to torture foes in what would seem like days, in just a matter of seconds. The victims would end up comatose in a matter of days due to their spirit breaking within the treacherous illusionary plane.
Itachi's Right Mangekyou Sharingan Dojutsu
With his right eye, he has awakened the highest level of fire release, the Amaterasu! This is the iconic black flames that extinguishes everything within the focal point of the user and will never stop burning, even if the target is incinerated into ashes. It is also said to be "the fires from hell," indeed a frightening dojutsu!
Mangekyou Sharingans Weakness
As Itachi quoted when fighting Sasuke,
"From the day you awaken it, your eyes begin a slow descent into darkness. The more you use them, they become sealed, till the Mangekyou eventually loses its light."
We have seen this process as fellow fans and avid enthusiasts of the Anime. Itachi, Sasuke, and even the legendary ancestor of the Uchiha Clan, all of them have awakened Mangekyou Sharingan, but eventually succumbed into either slowly loosing ones eyesight, to complete blindness. Itachi and Sasuke using the Amaterasu could cause a significant amount of strain to the user that would eventually lead to their eyes bleeding.
An original Mangekyou Sharingan puts a strain on the eye. The eye strain comes from the ocular muscles which are constantly being damage upon use due to the unique chakra the Mangekyou consumes. Using it too long will eventually weaken ones optic nerves which leads to blindness.
The only way to counteract this, which Madara stated, is by taking the eyes of another person, therefore resetting the eyes limit, and then removing it, since the body does not anymore recognize the users eyes as it’s own, effectively bypassing the limiter that the body would impose on it’s own eyes.