Uchiha Nagi pointed at the sword on the ground, "See? Except for some extremely southern and northern regions, the world is basically the same; the sun always rises from east to west."
"So, let's make a mark at the tip of the shadow."
After speaking, Uchiha Nagi picked up another Kunai and drew a mark on the ground at the tip of the long sword's shadow.
"Then, after a while, the shadow will move to the other side..."
Before long, the shadow cast by the long sword began to change with the sun's movement, shifting to another spot. Uchiha Nagi once again used a Kunai to draw a mark at the tip of the long sword's shadow.
Yukihime, as expected of someone who reads frequently, understood instantly, "I get it. The sun rises from the east, so the first mark you drew is west. Then, as the sun moves west, the sunlight shines in the opposite direction, so the second mark you drew is east, right?"
Uchiha Nagi nodded, "Except for that hour at noon when the sun is directly overhead, you can use this method to determine direction at any other time."
"See? Once you identify east and west, north and south become very easy to recognize."
Yukihime raised her hand and asked further, "What if there's no long sword? What do I use to figure out the direction?"
Uchiha Nagi looked at Yukihime, a little speechless: "..."
Kimimaro, on the other hand, laughed, "There are Kunai, or branches by the road, or even your own shadow. As long as there's a shadow, you can tell the direction, right, Teacher?"
Uchiha Nagi smiled and nodded, "You are teachable. This is one way to tell direction in the desert during the day. At night, you can use the stars."
"Also, in primeval forests, the extreme north, extreme south, and other places, different methods are needed. Geographical locations vary, so you can't generalize."
Yukihime, like a curious child, asked, "Why different?"
"Because the earth is round, so at different locations, the sun's angle and the magnetic field are different. Therefore, the methods used to determine direction are naturally different."
"Huh? How do you know the earth is round? Then why don't we fall off?" Yukihime kept pressing with different questions.
"..."
Uchiha Nagi suddenly didn't want to talk anymore. Explaining the first would require explaining the second and countless others. When would it end?
"If Teacher says it's round, then it's round."
Fortunately, there was Kimimaro, a blindly adoring follower. He didn't have so many 'whys,' otherwise Uchiha Nagi would go crazy.
Uchiha Nagi looked up at the sun in the sky. Kimimaro and Yukihime were already extremely thirsty, so he had no choice but to open another storage scroll and take out several gourds of water, handing them to Kimimaro and Yukihime.
"Don't let the sunlight hit your skin. Even if it's hot wrapped in clothes, it's better. That way, you can reduce your body's heat absorption and slow down water loss."
Yukihime gulped down a gourd of water in one go, her stomach bulging, but she still felt incredibly thirsty.
"So that's how it is. No wonder I felt so thirsty no matter how much water I drank."
Hearing this, Yukihime immediately used a white headscarf to tightly wrap her head. Kimimaro followed suit, wrapping himself up. Although his physique was good, it didn't mean he wasn't afraid of the heat.
After drinking water and resting for a while, the three continued their journey. It had been three or four days since they escaped the Daimyo's castle. A Ninja's pace of a hundred kilometers a day was not an issue; if not for Yukihime's hindrance, Uchiha Nagi might have been faster.
But leaving the oasis and entering the boundless desert region of the Land of Wind, their pace slowed significantly. They had to stop occasionally to compare the map and determine their bearings.
"Oh, Teacher, look! It looks like there's some kind of structure over there?" The sharp-eyed Kimimaro spotted the remains of a building not far away.
"Hmm, let's go there. Perhaps that's our destination for this trip—"
The three walked into the architectural remains within a ruin. The wind and sand here were severe, and many buildings were half-buried, which explained why many guides no longer knew the way to Rouran Country.
"Rouran..." Uchiha Nagi murmured, looking at the ruins.
"By the way, why do you insist on coming to Rouran Country, a small kingdom that has already perished? Is there some treasure hidden here?" Yukihime asked curiously.
"Hmm, I came to see. It's said there are treasures here..."
Although Kimimaro wouldn't ask, there was a hint of curiosity in his eyes. Traveling all the way to the Land of Wind, then sneaking into the Daimyo's castle to steal a map, going through all this trouble... because there was the Dragon Vein, a unique energy that Ninja could use.
Uchiha Nagi did not reply, but instead thought about the memories hidden deep in his mind. There was a guy named Mukade, who had plotted for a full six years, meticulously planning, before successfully making the Dragon Vein his own.
Then he transformed the Dragon Vein into a Chakra core battery, similar to a Tailed Beast, inexhaustible, draining Naruto's blue. Of course, at this time, Naruto had not yet learned Sage Mode, nor did he have the complete Nine-Tailed Mode.
Subsequently, Mukade, combined with his puppet jutsu, could recover no matter how he was attacked. Although his combat power wasn't strong, he was immortal and indestructible as long as his blue wasn't depleted, almost exhausting Naruto and Minato to death.
But it was enough to prove the terrifying magnitude of the Dragon Vein's energy. Uchiha Nagi wanted to see if, since the Dragon Vein could be used by people, could it be sealed into a human body like a Tailed Beast?
His own Chakra reserves were already huge, but after the battle with Orochimaru that night, he knew he still had some way to go compared to Orochimaru's blue. And Jiraiya's blue, and Tsunade's blue, were even greater.
Obito, with half his body made of white zetsu cells, and Nagato, their blue reserves were probably even more terrifying.
Who would refuse to have a little more blue?
"Water Release: Water Dragon Bullet Jutsu!"
Several water streams instantly converged into a small pool.
He tried to perform a Water Release jutsu and found it was several times less strenuous than in the desert, requiring less Chakra. This proved that there was more moisture here, indicating underground rivers.
"You two wait here. I'll scout around."
Uchiha Nagi pointed to the building. Although the ruined structure was very old, it was still fine for sheltering from the scorching sun.
Yukihime, hot and without any regard for her image, stuck out her tongue and immediately ran inside.
"Okay, Teacher." Kimimaro nodded and also went in to avoid the light.
Uchiha Nagi then made a few jumps, splitting into several clones to scout the surrounding terrain. While checking the central part of the ruins, he suddenly felt a strong sense of hostility and killing intent.
Since there was killing intent, it meant an enemy. Slowly, he drew his nichirin blade and Kunai... Swish—
Before the opponent could react, several Kunai with Exploding Tags were shot ahead to scout the opponent's hiding place.
Boom!!