That night Sasuke explained his plan to Hayami and got her approval. The next day after morning training of the kids, Sasuke was standing atop the castle roof overlooking the beautiful scenery around him. He was in normal clothing and not in his shinobi gear. He looked like a handsome man with short black hair. His hair cut was the same as the hair cut that modern soldiers of his former world would have.
Sasuke: Ok, time to get to work.
He made the hand sign and executed the jutsu.
[Shadow Clone Jutsu]
Poof and a clone appears besides him. The clone has 50% of his chakra. The clone took out his scroll, opened it and put his right hand on it. Smoke was released from the scroll, which was the sign that something was unsealed, the smoke enveloped his clone and when the smoke disappeared, the clone was dressed in complete black coloured shinobi gear with the black demon mask.
Sasuke: Get into Sage mode to recover 100% of your chakra, then leave. Try to complete the mission even if its dangerous. Only give up after trying everything.
Sasuke said this because even if its dangerous, he wanted to complete the mission and save time. If his clone failed then he might have to do the mission himself depending on the circumstances.
[Sasuke Clone]: Don't worry. Leave it to me.
The clone sat down and concentrated. He then entered sage mode and started to recover his chakra to reach 100%. After 10-15 mins, he was done. He got up, nodded at the original and disappeared from the roof.
Sasuke: Now then, I hope my clone is enough.
...
The next day, multiple groups entered the capital of Hayami's territory. Hayami resided in the castle of this town. All the groups that have arrived, have the same objective. It is to find the location of the mines. The groups dispersed to collect information.
Sasuke's clone also reached one of the villages at this time. He saw the destroyed village and the bodies in scary conditions.
Sasuke's Clone: What the fuck? What has happened?
He then started his own investigation as well.
...
That evening, in Hayami's castle town, inside an inn. One of the teams sent by Hikari was gathered in a small room to share information. The team consisted of one member each from the Hyuga, Aburame, Inuzuka and the Uchiha clan. The ages of the team members were between 16-30 with the Uchiha being the oldest.
Uchiha Leader (Male): Let's share what we have found out so far. Nobody talks about the mines. There are people who go away for 2-3 weeks. When they return although most look clean but many appear as if they have laboured in a mine. These people always go to the castle before disappearing for 2-3 weeks.
Inuzuka Member (Female): The people that return after 2-3 weeks, even if they look clean, have smell of chakra metal or gold on them.
Inuzuka Dog: Woof.
Hyuga Member (Male): I can't look inside the castle with my [Byakugan]. There are seals on the castle walls that stop my eyes from penetrating and looking through them. Also, I have noticed that the people that come back after 2-3 weeks have a seal on their left arm close to shoulder. The seal looks like a thunderbolt. I think it is probably a curse mark of some kind.
Uchiha Leader (Male): That curse mark is probably the reason why people don't talk about the mines.
Aburame Member (Female): My insects can't enter the castle as well. If they try then they are burned. I think there is an invisible barrier around the castle in the shape of a dome. The barrier burns the insects and I don't see even birds flying into it.
Uchiha Leader: I see. So there are counter measures in place even against [Byakugan] and insects. That brat is definitely smart.
Hyuga Member: What do we do now? Do we meet other teams?
Uchiha Leader: No, they might have found the same information as well. I will meet the other team leaders tomorrow and see whether anyone know more than us.
Aburame Member: What is our next plan of action?
Uchiha Leader: Try to find out more information. Maybe there is something we missed or a family member of a miner might know something. Either way, try to find out any new information. Now let's sleep. As we talked before we have two rooms, so we pair up and each pair sleep in one. We will also take turns sleeping. Don't drop your guard. We are in enemy territory.
...
At the same time, in another inn. The squad sent by the old diamyo consisting of members from Nara, Yamanaka, Akimichi, Senju and Sarutobi was also having their meeting. They have ages between 20-35. With the Sarutobi member being the oldest and the Senju member being second oldest at 28.
Yamanaka Member (Female): I took over the mind of a bird and wanted to fly over the castle to see inside but other birds attacked me the moment I got inside the mind. It is as if the birds are already in someone's control.
Sarutobi Member (Male): Then it is not something new. We know Kouske Shiru can do that.
Nara Member (Female): You don't understand. She is trying to say that all the birds are already under the control of Kouske Shiru. I was the one who asked her to posses a bird and view inside the castle as it was weird to me that even the birds weren't flying close to it. From this we know, Kouske Shiru has even taken the birds into account. I saw a group that looked like it returned after 2-3 weeks as we have found out. I followed the group to a restaurant. At the beginning they didn't talk about their work or what happens in the castle, but one of them became drunk and he was about to say something, then he suddenly stopped speaking and became still as a statue. His group members helped him sit down and one of them said the words, "That is why we shouldn't talk about work while drinking". Meaning there is something that stopped that drunk worker from saying what he wanted to say. Kouske Shiru is from a clan that was proficient in sealing. From this I can hypothesis that he has planted cursed seals on the workers so that they can't leak information.
Akimichi Member (Male): I was also busy gathering information. I went to all the restaurants to gather as much information as I can.
The Akimichi clan member said was trying to stop his saliva from leaking.
Yamanaka Member (Female): You spent the whole day eating in different restaurants? (Said while showing her annoyance)
Nara Member (Female): What am I gonna do with you?
The Nara member smacked her head with her left hand showing she was fed up with the team member's behaviour.
Akimichi Member (Male): Wait, Wait, I haven't finished. I really gathered good information. You should be thankful that I was doing it otherwise you guys wouldn't have known what I am about to share.
Senju Squad Leader (Male): Let him speak.
On the squad leader's order the Akimichi was finally allowed to speak and spared a lecture.
Akimichi Member (Male): I saw 3 different groups trying to fish for information. All three had a Ninken(Ninja Dog) and everyone in those groups have covered themselves completely with a cloak. I think they were shinobi groups fishing for information same as us.
Sarutobi Member: Well that wouldn't be weird. We aren't the only ones after the mines after all.
Nara Member: Still, just what kind of amateurs won't disguise as normal folks to collect the information.
Senju Member: Even if they are openly collecting information, it isn't weird. Shinobis pass through not only this but all the towns all the time after all.
Nara Member: Still if they are doing this then that makes them our competition. If the 3 teams have Ninkens then there is a high chance that all 3 teams belong to the same group or alliance. They split to gather information.
Senju Member: What should we do to gather more information? Should we grab a miner and have our Yamanaka member peak in his mind?
Nara Member: That is dangerous. There is a high chance that Kouske Shiru has put barriers and genjutsu traps in the minds of the miners. After all, he took measures with the birds and the curse seal.
Yamanaka Member: Even if there are traps in miners mind, I am confident that I can pass through them.
Senju Member: She is right. Also, don't forget each one of you is among the elites of your respective clans. The Yamanaka train for these things. We have to take this risk. Let's grab a miner tomorrow and execute this plan.
Sarutobi Member: I will try to get information about the other groups.
Senju Member: Go to the restaurants with our Akimichi friend here. Eat together and mingle as a cover. Don't blow your cover.
Sarutobi Member: Alright.
Akimichi Member: Yes Sir (Drool dropping from the side of mouth).
...
At the same time, in a room of Hayami's castle. Sasuke was sitting on the floor and had his eyes closed. His eyes has shading showing that he is in Sage mode.
Sasuke: I sense 39 chakras greater than normal folks. They are probably shinobis.