In a large tree within the Uchiha compound:
"Stay here for a while," Shishou said. "I need to leave for a bit."
He placed a sealing talisman on Mikoto's forehead, restricting her movements. This tree had a perfect vantage point to see everything happening within the Uchiha compound.
"What are you doing?" Mikoto asked, puzzled by her restricted state.
"This is to prevent you from running out to see Sasuke while I'm gone," Shishou replied. "Open your mouth."
"You're going to gag me too?" Mikoto was surprised.
"Be good," Shishou said.
"Alright," Mikoto complied.
After gagging Mikoto, Shishou set up a barrier around her to prevent discovery and left a shadow clone for backup before disappearing.
Next, he retrieved Uchiha Izumi from the Land of Iron, using similar methods to restrain and hide her.
Then, Shishou found another shadowy spot and rubbed his hands together in excitement. "The show is about to begin."
...
Uchiha Sasuke was eagerly running into the Uchiha compound, ready for some training.
Sasuke!
Seeing Sasuke, Uchiha Mikoto felt a surge of excitement.
On the other side, Uchiha Izumi frowned, reminded of her desire for vengeance against Uchiha Itachi.
Just as Sasuke entered the compound, he was kicked into the air.
"You foolish little brother, you're just as weak as always," Itachi said coldly, stepping out from the shadows. "I taught you to never let your guard down."
He wore black clothes instead of the Akatsuki uniform, indicating he was not acting on Akatsuki's behalf.
Even in front of his younger brother, he showed no mercy.
Behind Itachi stood Biwa, also dressed in black, shaking his head at Itachi's cold demeanor.
"Sasuke!"
"Itachi!"
Seeing Itachi kick Sasuke, both Mikoto and Izumi's Sharingan activated, filled with anger.
Had they not been restrained, they would have already rushed out to confront Itachi.
"Itachi!" Sasuke screamed, rushing at his brother.
"You are still as foolish as ever," Itachi easily evaded Sasuke's attack, grabbing his arm and kicking him in the stomach. Sasuke spat blood and writhed on the ground in pain, crying out.
Sasuke!!
Mikoto wept as she watched her son in agony, struggling desperately against her restraints.
Izumi, too, was filled with rage, her eyes locked on Itachi with a murderous glare.
As Itachi looked at Sasuke writhing in pain, a pained expression crossed his face. He closed his eyes for a moment. When he opened them again, his resolve was evident.
Remembering Shishou's instructions to make it as painful as possible, Itachi's expression turned cold.
He walked over to Sasuke and stepped on his left hand.
"Ah!" Sasuke screamed in pain.
Itachi then grabbed Sasuke's left hand and twisted it until it snapped.
No!!!
Mikoto's heart broke as she watched. Her Sharingan spun rapidly, her emotions a turmoil of rage, regret, and killing intent.
On the other side, Izumi's mind was flooded with memories of her family's massacre at Itachi's hands. Her breathing quickened, and her Sharingan also spun rapidly.
Crack!
Itachi snapped Sasuke's left hand, causing him to pass out from the pain.
Itachi then grabbed Sasuke's right hand.
Sasuke!
Mikoto screamed internally, her Sharingan spinning faster and faster until she finally passed out, unable to handle the strain of awakening the Mangekyō Sharingan.
Shishou, catching her as she fell, frowned in thought. He hadn't anticipated Mikoto fainting just as she was about to awaken her Mangekyō.
Laying Mikoto down gently, Shishou moved to Izumi's side, determined to ensure her success.
Crack!
Itachi snapped Sasuke's right hand.
Izumi's breath caught as she watched, her mind flashing back to the night of the massacre, seeing Itachi kill her family again and again.
Itachi!
Her eyes filled with tears of blood as her Sharingan transformed into a unique black sun pattern.
"It worked!"
Izumi, a genius who had awakened the three-tomoe Sharingan before thirteen, successfully awakened her Mangekyō under Shishou's genjutsu. Delighted, Shishou knocked her unconscious with a hand chop.
"Let's go," Itachi said to Biwa , seeing Sasuke unconscious. "He still hasn't awakened his Sharingan."
As Itachi and Biwa began to leave, they stopped, sensing someone.
"Are you Uchiha Itachi?" Kurenai Yuhi stood at a distance, eyeing the unconscious Sasuke warily.
Today, being the last day of May, she had planned to wait for Shishou in the forest outside Konoha. On her way back, she heard Sasuke's screams and stumbled upon this scene.
"Why is she here?" Shishou, holding the unconscious Mikoto and Izumi, was speechless.
He noticed Kurenai always seemed to stumble into such situations. First, she interrupted him and Tsunade, then she witnessed Biwa and Shennong exchanging bounties, and now this.
Her luck was truly unfortunate!
Still, it might be good for her to face reality sooner rather than later, preventing her from wasting more time on simple genjutsu.
With this thought, Shishou laid down Mikoto and Izumi, ready to step in as the hero.
Note: If you are interested, you can read up to chapter 530+ at patreon.com/Betek.