It's not that Kakashi doesn't trust Mokgetsu, it's just that Kakashi is curious about more details.
But to Kakashi's disappointment, he didn't find any records about the Rinnegan's abilities—only some myths and legends.
Having already come, Kakashi decided to look up some materials on the Tailed Beasts, but he still didn't find much, still couldn't figure out why the Tailed Beasts go on rampages.
After leaving the library, Kakashi went to find Might Guy.
After returning from Loulan, Kakashi had looked for Might Guy, but that time Guy was out on a mission, so Kakashi didn't find him.
"My dearest rival, are you challenging me? I've been waiting for this day for a long time!" Might Guy asked excitedly.
It's been over half a year since he last defeated Kakashi, and Might Guy had long wanted to battle Kakashi again.
During this half year, Might Guy never relaxed, always keeping up with his training. He had a feeling he was just one step away from the Fifth Gate.
"I'm not here to fight you, I have something to discuss," Kakashi shook his head and replied.
He wanted to share information from the future with Might Guy, hoping to work together to change destiny.
Hearing Kakashi say it's not about fighting, Might Guy's face instantly changed from excitement to disappointment. He had already thought about how to start the battle.
"If you really want to be challenged, it's not out of the question," seeing Might Guy so disappointed, Kakashi thought for a moment and said.
"It seems a battle full of youth's vigor is inevitable." Might Guy laughed heartily and gave Kakashi a thumbs-up, his bright white teeth sparkling in the light.
"But it's limited to rock-paper-scissors." Kakashi added.
A Might Guy who was full of energy looked defeated all of a sudden, like a withered cabbage.
"Rock, paper, scissors!"
Might Guy, though slightly disappointed, still took this rock-paper-scissors challenge seriously.
"You won." Kakashi raised his scissors hand and said.
Might Guy looked at his fist and sighed. He still preferred a full-contact fight with Kakashi; winning that would be more satisfying.
Silently adding this victory to his total wins against Kakashi, Might Guy followed Kakashi to a secluded grove.
"We took on a mission to investigate the minister of Loulan and encountered shinobi from the future..."
Kakashi first briefly explained the events leading to their encounter with Uzumaki Naruto and then went on to detail the information they gathered about the future and the Akatsuki intel acquired in the Land of Rain.
Might Guy was very surprised that Kakashi and his group encountered ninja from the future, but he immediately believed Kakashi without any doubt.
"To change the future, we need your strength," Kakashi said seriously.
"This is the very essence of why I train to become stronger." Might Guy replied with a radiant smile.
Teacher Mokgetsu, Obito, Nohara Rin, all were comrades Might Guy acknowledged. He would give everything to protect them.
"Don't tell anyone besides us about this matter," Kakashi reminded.
Might Guy nodded solemnly.
Then, Might Guy and Kakashi went to the Southern Border Forest. Kakashi needed to discuss something with Mokgetsu's other students, which was also why he didn't agree to fight Might Guy earlier.
"To help everyone improve faster, I propose having a field test every three months, and the last two will face punishment." Kakashi shared his idea.
To others, they might already be considered super geniuses with such strength at the age of ten, but Kakashi thought it wasn't enough. This level of strength was not enough to change history; they needed at least the power of Uzumaki Naruto or Yamato.
"Rin, you don't have to participate in this since you're mainly focusing on medical ninjutsu." Kakashi said to Nohara Rin.
When estimating fighting strength, Kakashi considered Nohara Rin an ordinary Chunin, and a Medical Ninja's chakra should be saved for healing.
Nohara Rin nodded helplessly. She would have liked to join in, but the gap in strength made it meaningless.
"I agree, and I think today would be great; let's start our first field test right away!" Might Guy was the first to support Kakashi.
"I think it's doable." Shisui nodded in agreement.
Although Shisui currently didn't have the confidence to defeat any of Kakashi's group, he believed this was more beneficial for improving his strength.
"I don't mind either, but what's the punishment?" Obito asked curiously.
"It's simple, whatever each person hates as a punishment, that's what it is." Kakashi responded.
Due to individual differences, what might be a punishment for some could be a reward for others. Kakashi felt individualized punishments were needed.
Obito's face showed a hint of unease as he quickly spoke up, "I really hate..."
"For example, Obito, you dislike studying and doing worksheets, so your punishment will be studying and doing worksheets." Kakashi interrupted.
"I think I hate green peppers more; how about changing it to eating ten green peppers?" Obito tried to change the punishment.
"After all, I know myself best."
Kakashi gave Obito a calm look, "If you really hated eating green peppers more, you wouldn't suggest a change."
Of course, Obito understood himself well, but he was also capable of deceiving himself.
"Worksheets really are Obito's weakness." Nohara Rin remembered Obito's look of despair when punished with worksheets and covered her mouth, chuckling.
"With his level of knowledge, doing worksheets is indeed a big challenge." Kakashi quickly added another jab.
Obito blushed, trying to argue, "I scored eighty in the science section of the Chunin Examination, you know, eighty!"
Although that was with a little help from Mokgetsu, his effort counted too.
"So you're saying you're not afraid to do worksheets, then you shouldn't have asked to change." Kakashi continued with a smirk at the red-faced Obito.
Obito didn't know how to argue anymore and could only curse Kakashi in his mind before accepting this as his punishment.
Kakashi was tough on Obito and himself too, soon volunteering his punishment.
"If I'm in the last two, I won't argue with anything Obito says for a whole week." Kakashi stated firmly.
To Kakashi, that punishment was pure torture, knowing Obito would likely spew nonsense non-stop.
With Obito and Kakashi setting an example, Shisui and Might Guy didn't hold back either, giving themselves some suitably uncomfortable punishments.
Then it was time for the actual combat practice.
The four drew lots to decide their first-round opponents. The two who lost in the first round would face punishment, and the two winners would battle again, with the victor becoming Mokgetsu's strongest disciple for the next three months.
Since she didn't have to participate in the battle, Nohara Rin handled the chores and helped Obito and the others draw lots.
"Shisui is number one, Obito number two, Kakashi number three, Might Guy number four," Nohara Rin announced the draw results.
"My dear rival, this is the bond between us!" Might Guy laughed, giving Kakashi a thumbs-up, and his previous disappointment was wiped clean.
Kakashi's expression turned serious. No matter how strong Might Guy was, he had to win this battle, or he couldn't imagine how smug Obito would be for the next seven days.
Shisui and Obito exchanged glances, both filled with fierce fighting spirits.
Shisui really wanted to win, not just because of the punishment, but due to his competitive nature.
Shisui was the youngest of Mokgetsu's disciples but was the one who started learning from Mokgetsu the earliest. He was used to being the strongest, not the weakest.
"Obito, your Breath of Flame Chakra Mode is strong, but you don't know I've already mastered Armament Aura, right?" Shisui's confidence came from his mastery of Armament Aura.
From the beginning, Shisui's progress in Armament Aura was far ahead of the others, and while others were still clueless, Shisui was already able to sometimes use Haki successfully.