It took Sasuke three days to turn on the video game console. The cursed seal was a hindrance when drawing out chakra, but he had managed to struggle through and learn how to manipulate his chakra into lightning release. The back of Sasuke's neck was wet with sweat as the game glowed to life. There was a soft chime. A two-dimensional sprite of a shinobi appeared in the center of the screen.
"Hey, you got it, not bad," said Kakashi. He was sitting on the other side of the room, supervising Sasuke's chakra manipulation, though admittedly part of his attention was focused on the open Make Out Paradise novel in his hand. "You need to make sure your little guy there avoids all incoming attacks."
The controls were simple enough. Sasuke moved his character around the screen, dodging shuriken sprites that originated from all angles. The shuriken onslaught increased in speed, and the screen was becoming a blur of flashing light.
"The game increases in difficulty the longer you play, both in terms of shuriken speed and required chakra," said Kakashi. "Keep it going for ten minutes without getting hit."
Sasuke's reflexes were sharp enough to move his character away from incoming shuriken—he excelled at challenges of speed and precision ever since he was a young boy—but the additional strain of continuously manipulating chakra into lightning release and suppressing the cursed seal was too much to maintain. The game console's screen faded to darkness before Sasuke could play for the full ten minutes. He failed to keep the battery charged.
On his second try, Sasuke made it four minutes before Kakashi sensed the energy of the cursed seal leaking through. He broke Sasuke's concentration with a flick to the ear and had him restart the game.
"Don't overdo it," said Kakashi. "This training takes a toll on your chakra, and the more chakra you use the harder it will be to resist the cursed seal."
Sasuke took a few minutes to meditate. He didn't want to sleep. He hadn't slept much since the Forest of Death because of the nightmares. His dreams had grown increasingly lifelike and violent, and within the last couple of days they had drifted into his awakened consciousness in the form of hallucinations.
The next morning Kakashi brought Sasuke to an underground training gym. Physical conditioning was a welcome change from the ceaseless chakra manipulation exercises. Sasuke's primary focus was speed and agility—Kakashi warned him of the fortitude and persistence of Gaara's sand, but explained that Rock Lee was able to outrun it and land solid blows.
"Lee took years to hone that level of toughness and agility, and his body still sustained significant damage from overexertion," said Kakashi. "You on the other hand have less than three weeks to train."
"Not your most optimistic pep talk, Kakashi-sensei," said Sasuke.
"Well, you do have an advantage over Lee," said Kakashi. He gestured to his own left eye. "The Sharingan. I observed Lee's taijutsu form that was effective against Gaara, and I've sparred with Lee's sensei, Might Guy—he utilizes a similar fighting style. I can show you the techniques so that you can copy them with your own Sharingan."
Kakashi demonstrated the moves that he had picked up from Lee and Guy, as well as a smattering of other taijutsu forms that he judged would compliment Sasuke's current abilities. Sasuke had little difficulty memorizing Kakashi's movements, but mimicking the techniques in practice was a greater challenge. Without the muscle and stamina that Lee and Guy had attained through arduous discipline, Sasuke could only perform their techniques at semi-speed for short bursts before exhausting himself.
"That's enough for today," said Kakashi. Sasuke was soaked with sweat, and his lungs heaved to suck in oxygen. He dropped to one knee. "Good first day, but if we go any longer at this you're bound to injure yourself." Kakashi helped Sasuke up, and they made their way back through the bunker. Incredible… If I tried training with the Sharingan like that for so long I wouldn't be able to move for days. Being a pure-blooded Uchiha, and a child prodigy nonetheless, Sasuke's body had a far greater potential than Kakashi's in terms of handling the Sharingan.
Four days later Sasuke beat the chakra-charged video game. His hands twitched from the continuous chakra output, the console chiming victoriously.
Kakashi set down his book. "Oh, high score!" he laughed. "It's finally safe for you to attempt the Chidori."
"Safe?" said Sasuke.
"It takes a lot of power and precision to transform the chakra," said Kakashi. "If you're careless, you could lose your arm, or even die. Your completion of the game proves that you can draw and transform a decent amount of chakra without losing focus."
Sasuke thought back to Kakashi's demonstration of the Chidori on his first day of training—the jonin had concentrated a massive amount of lightning chakra in and around his hand. Sasuke memorized the technique the moment his Sharingan had a glimpse of it, but executing the ninjutsu was another matter. He put his arm out and cleared his mind, summoning more and more chakra into his palm, the air around him growing heavy with static electricity. His hand was hot. Sasuke felt as though he was wrestling with a storm cloud, fighting to corral pure lightning. A jolt of pain shot through Sasuke's arm, and Kakashi stepped in to grab him by the wrist, breaking his concentration and releasing the technique.
"You're not there yet, don't force it," said Kakashi.
Sasuke cradled his arm. He tried to take a step, and stumbled into the wall, his vision blurring. The fatigue was overtaking him, he had pushed his body and mind to its limits over the past week. Kakashi had an on-site medical shinobi confirm Sasuke's vitals were safe, then they let Sasuke sleep.
That night Sasuke's nightmares were worse than ever. He dreamed of his clan's massacre, reliving each gory moment. But it wasn't only Itachi that stood over the corpses of their parents, he was joined by Orochimaru. Itachi and Orochimaru descended on Sasuke. You are weak…
"No!" Sasuke woke in a flash, sitting straight up in his cot. He could barely breathe, still reeling in the shock of his visions, and in his elevated state Sasuke put out his arm and focused the chakra that boiled within him. No, I'm not weak anymore. Not like that. Lightning chakra crackled in his hand. The chakra chirped, resonating throughout the room. It seemed to have a life of it's own. He marveled at the Chidori in his palm.