Kimimaro was standing in some wasteland between two mountain ranges somewhere in the Land of Fire.
'It's time I get back to Konoha, my training here is finished' he thought.
He managed to obtain the Perfect Sage Mode a while back. But he wasn't satisfied with it too much initially.
He realized that to enter that Sage Mode he would need to meditate for some time before being able to enter it. That was his biggest problem.
He needed to somehow make a switch into himself whenever he wants to enter the Sage Mode.
That's why around a month ago he had come back to Orochimaru's base to meet with his old friend Jugo.
He took some of his DNK and implanted it in himself as he had always done before. He then made a biological switch, activating these cells, only when he wants.
So in this way, he managed to bypass this restriction.
But there was one more restriction. He could only use his Sage Mode alongside his Tenseigan mode. His Tenseigan Chakra mode burns chakra like crazy, and his Sage Mode replenishes it like crazy.
If he used his Sage Mode alone he could risk going crazy like Jugo or turning into a snake. And he doesn't want that. And if he used Tenseigan chakra mode alone, he would run out of all chakra in 3 minutes. So in this way, these two powers are in perfect synergy with one another.
The only thing left for him to in regards to his strength would be to seal the Ten-Tails inside himself.
But that'll come naturally later in the plot, so he doesn't have to do anything now besides learning Fuinjutsu of course.
He learned the basics of it in these three months, but he'll continue to learn it for years, every day a little. After all, he has many years before he needs to use it on the Ten-Tails and Black Zetsu.
For now, he planned to go back to Konoha and enjoy his time around doing whatever the hell he wants there. He'll maybe go into other villages as well.
He's probably the strongest person on this planer right now after all.
But you don't need to be weak in order to enjoy battles. He will always use the minimal amount of strength necessary when dealing with his opponents. So that he could enjoy them more.
Now should be the time, when his clone would reverse summon him. He's waiting for that.
It happened then. He was reverse summoned into Konoha. He asked his clone "What happened when I was away?"
His clone replied "A lot of things happened. First like you predicted they all thought it was Danzo. But Danzo locked himself down in his underground base. Then they called Itachi Uchiha back. It was a tough battle. But in the end, they managed to kill Danzo. I'm not sure if Itachi is alive, but Hiruzen remained the Hokage"
"What happened to The Root forces?" he asked?
"Some joined Konoha forces, some died in battle, some went into the retirement" clone answered.
"Any news from other villages?"
"No, they didn't attack Konoha, they don't want to interfere with the current status quo"
"Nice, thank you for your services" he dissolved the clone. Then laid on the bed preparing to sleep.
'What am I going to do tomorrow' he thought as he drifted to sleep. He was exhausted, so he planned to sleep straight 24 hours.
__________________________________________
Nearly three months ago.
Somewhere in a dark cave outside of the prying eyes of the normal world. There stood many different holograms on different stone statues. They were all wearing the same coats. Black with red cloud patterns.
They all looked very unique and different.
The one with weird patterned eyes and piercing spiked hair asked indifferently "Zetsu report on what happened at Konoha"
Zetsu started speaking in his weird voice "...Well, it seems like it's Danzo gone crazy. He used his personal summon to attack the village on the one side. While he probably took Sasuke Uchiha from the other side."
Itachi flinched a little bit at that. If not for this hologram they'd see his messy look. He looked like a real mess right now.
He looked like he could die at any moment.
'Sasuke... what on earth happened to you' he thought. Even though he managed to defeat Danzo in the end, he still denied it till his death.
He also had a hunch like it was not the whole story about what happened to his brother.
"This doesn't affect us in any way. Continue with the plan. You're all dismissed" The leader, Pain spoke.
They all dispersed after that.
After the meeting was over, near the river, somewhere in an unknown place.
There stood a tall shark-looking blue man, near him the black-haired Itachi Uchiha.
Kisame looked surprisingly solemn and asked the teen "How much time do you have left?"
"I don't know, but I can't depart yet! I need to realize the full story about what really happened to Sasuke!" Itachi replied weakly, then coughed.
'I failed you, brother, I'm sorry' he thought as tears started forming in his eyes again.
"Then get yourself together!" yelled Kisame.
"Even if you're weak now, I'll help you. I promise I'll find out what happened to your brother." Kisame said determinedly.
'Kisame...' Itachi thought.
"Didn't Orochimaru want to steal your Sharingan before? Maybe he was behind this. Let's go and pay him a visit now" Kisame said. Soon the two of them left.