Lug's back was hunched under the weight of the heavy stone he carried.

His pocket, filled with coins, jingled with its usual metallic sound.

Xam supervised this new training session, and Lug would alternate between three activities in the camp: sparring with Xam, weightlifting, and participating in the Sunday assault.

The stone he carried on his back weighed 30 kilograms. It was an oval-shaped stone used for soldiers' training, made of psychic energy and materialized by the commander. According to the Sage, carrying psychic weights was the fastest way to progress.

That morning, the Sage had given Lug a lecture on the relationship between a physical body and psychic energy.

"When you carry a psychic object, you feel its weight, and your body uses energy, right?" asked the Sage. Lug nodded. "That weight comes from a mix of your physical and psychic energy, as well as the object's energy. Lifting a psychic weight uses 60-70% of your energy, while the psychic object loses only around 30%."

Lug was puzzled. "So when I hold a psychic object or hit a ghost, I lose more energy than the psychic body I touch?" The Sage nodded. "Yes. Your body does most of the work to make contact with a psychic body."

The Sage continued, "If a dense psychic object touches you, your body instinctively translates psychic contact into physical contact. But If a ghost punches you, your body translates only the nerve shock. You'll feel pain, but you won't get injured."

Lug recalled his painful experiences and shuddered. "Is this the ‘intelligence’ from my body that stops me from getting hurt?" he asked. "Yes, its main goal is your survival," the Sage confirmed.

"For your training, you'll carry psychic weights. They'll have the same effect as real weights and help deplete your psychic energy," explained the Sage. "Why is that good?" asked Lug. "Using your energy more widens your channels, so you can use it more easily and in larger quantities," the Sage summarized.

Lug argued, "But if my psychic energy is also used, I'll tire faster and train for a shorter time." The Sage replied, "Endurance is important, especially for you. Your body can become a war machine, and that's what I hope for you." Lug's memory faded at that moment.

He lost his balance and fell to the ground, completely distracted. The stone fell on his head, but fortunately, he only felt the pain from the impact.

"You'll never progress if you spend your time being elsewhere!" Xam scolded him, standing with crossed arms. He wasn't wearing his armor. "By the way, take off your sweater and your T-shirt," Xam added after observing Lug for a moment.

"Huh? Why?" asked Lug, a little disoriented as he got up.

"Why? Seriously? You have skin, a body that can feel the sun's warmth, sweat dripping, and aches in your muscles. You don't realize how lucky you are. Get rid of all that fabric! You're lucky I'm not making you strip naked!" the ghost said seriously, frowning and pointing at Lug.

Lug reluctantly obeyed. He wasn't comfortable with his body. He was thin, with pale skin and some unappealing red spots here and there on his shoulders. Once shirtless, he went to pick up the heavy stone again. Xam looked satisfied.

The training continued for a few more hours until Xam suggested a new exercise for Lug.

"We have wooden poles at the back of the camp for improving balance. You'll use them," Xam said, motioning Lug to follow him.

Soon, they stood before a small forest of about ten poles. Some were three meters high, while others approached seven meters. They were made of psychic energy, which brought up a question Lug had yet to answer.

"What happens if I climb an object made of psychic energy? Can I fly?" he wondered, looking at the poles.

Xam gently nudged Lug forward. "Climb up there and jump from one pole to another, starting with your feet. When you have more muscle, you'll move on your hands."

The poles were spaced about 50 centimeters apart, sometimes a little more, sometimes a little less. The idea of jumping from one pole to another was already daunting enough, but jumping while standing on his hands? Lug couldn't even imagine that being possible. Nevertheless, he began to climb the smallest pole.

He placed his hands around the pole, its diameter wide enough for Lug's hands to touch while gripping it. He positioned his legs around the pole, using them for support as he climbed. After several arm movements, he reached the top of the pole, sat down, and caught his breath. However, he couldn't catch his breath for long. Being on the pole exhausted him.

He decided to descend, but before doing so, he closed his eyes and altered his energy flow to no longer see the surrounding psychic energy. When he opened them again, everything had vanished – the tents, the soldiers, and even Xam. The pole that held Lug in the air was also gone, and he was left suspended. The sensation of vertigo nearly made him fall. He reactivated his ability to see energies, then climbed down calmly.

Upon reaching the ground, Lug vomited. The effort had been too intense.

Xam patted him on the back. "You did well today. Come back tomorrow, and you'll have your first real fight."