At the beginning of the yellow extreme boundary, the "air pool" has increased by tens of times and is as big as a basketball.

  The true energy in the air pool was still very rare, only as big as an egg, less than one tenth of the capacity of the air pool.

  Only by filling up the true energy in the air pool can one break through to the next realm, the middle period of Huang Ji.

  Zhang Ruochen sat down with his legs crossed, closed his eyes, and the divine seal of his brow opened as he began to cultivate the first layer of the Nine Heavens Emperor Scripture, "Tai Huang Huang Jing Tian".

  True Qi flows out from the Qihai and circulates throughout the body along that one meridian which has been opened up.

  As the true energy inside his body circulated, Zhang Ruochens body was like a whirlpool, slowly absorbing the spiritual energy between heaven and earth.

  Heaven and earth spiritual energy, flowing into the brow of the divine martial mark.

  Shenwu Seal transforms the spiritual energy of heaven and earth into true energy, storing it in the Qi Pool. True energy flows out from the Qi Pool, along the meridians, circulating throughout the body.

  When the true Qi runs one cycle inside the body, it is called a Small Heavenly Cycle.

  After running for nine weeks, when Zhang Ruochen opened his eyes again, he found that the amount of true energy in his body had doubled, reaching one-tenth of the capacity of the air pool.

  If other warriors knew that they could double their internal qi in such a short period of time, they would definitely be overjoyed.

  However, Zhang Ruochen was somewhat dissatisfied. "After cultivating for nine cycles, Ive only increased my true energy by this much. Its too slow. If I could get a spiritual crystal, my cultivation speed would be able to increase by another fold."

  Its worth noting that Zhang Ruochen cultivates the Nine Heavens Divine Emperor Scripture, and his speed of absorbing true energy is originally faster than those warriors who cultivate lower-level martial arts.

  The current cultivation speed naturally made him very dissatisfied.

  If one can obtain a Spiritual Crystal, their cultivation speed will increase greatly.

  Spirit Crystal, formed by the gathering of spiritual energy into a crystal stone.

  You can dig up "natural spirit crystals" in the underground ore veins, or you can kill barbaric beasts and excavate the "acquired spirit crystals" from their bodies.

  The value of a single Spirit Crystal is generally equivalent to that of one thousand silver coins, and only the princes and nobles or the geniuses cultivated by the great families have the opportunity to obtain it.

  One thousand silver coins is an astronomical figure for Zhang Ruochen and Lin Fei now, its absolutely impossible to afford.

  "Spirit Crystal"

  Zhang Ruochens heart moved slightly, and he immediately took out the white date-shaped crystal that had been hanging on his body, holding it in the palm of his hand.

  Will this be a spirit crystal?

  The true energy in his body circulated, and the divine martial mark between his eyebrows immediately appeared, transforming into a coin-sized circular glow.

  A white aura shot out from between his eyebrows and struck the surface of the white crystal stone.

  "Wow"

  On the surface of the white crystal, four ancient characters emerged.

  Too weird

  Zhang Ruochen had never seen such characters before, but he recognized the four words at a glance - "Time Space Crystal Stone".

  It is worth noting that in his previous life, Zhang Ruochen had also infused the white crystal stone with true energy, but he had never activated the text on its surface.

  "In my previous life, my cultivation was hundreds of times stronger than it is now, yet the white crystal stones surface didnt display any text. In this life, with a mere early-stage Yellow Extreme Realm cultivation, the white crystal stone actually changed. This proves that its not because of the true energys intensity, but rather its attribute."

  For example, a warrior with the Blazing God Seal, using fire-attribute spirit crystals will have the best effect, and can reach three times the cultivation speed. Using ordinary spirit crystals can only reach twice the cultivation speed.

  In nature, ninety percent of spiritual crystals have no attributes. Just like ninety percent of warriors can only evoke attribute-less martial arts marks.

  "Could it be that the Divine Martial Seal I activated also has some sort of attribute, which just so happens to match this Time-Space Crystal? Wait a minute, what is this Time-Space Crystal?"

  Zhang Ruochen was the son of Emperor Ming in his previous life, with a broad vision and knowledge of many attribute crystals, such as Scarlet Flame Crystal, Dark Ice Crystal, Thunderbolt Crystal, and Evil Blood Crystal. However, he had never heard of a time-space attribute crystal.

  Because time and space are fundamentally beyond human control, even gods cannot shake time and space, and must follow the rules of time and space.

  Just as Zhang Ruochen was still very puzzled, a halo appeared on the surface of the Time-Space Crystal, transforming into a whirlpool.

  The whirlpool continued to grow larger, enveloping Zhang Ruochens body.

  Zhang Ruochen only felt a dizziness, and the next moment, he came to a closed space, heavily falling onto the hard ground.

  Fortunately, he completed the marrow washing and reached the early stage of Huang Ji, his body strengthened a lot. If it were his previous fragile body, falling like this would have probably killed him.

  Zhang Ruochen got up from the ground, moved his sore muscles and bones, and began to observe the surrounding space.

  This space is completely sealed and cannot see doors or windows. The height of the space is about ten meters, and the length and width are also about ten meters.

  "How did I end up like this? Where did I come from? And where is this place again? Hmm, theres a stone pedestal over there."

  In the entire space, there is only one stone platform.

  On the stone pedestal was a rolled-up painting and a silver iron book. There were no other things besides these.

  Zhang Ruochen went to take that painting first, but that painting was incredibly heavy, as if it were connected to the stone pedestal as a whole. No matter how much strength Zhang Ruochen used, the painting didnt budge at all.

  Since he couldnt pick up the painting nor unfold it, Zhang Ruochen could only temporarily give up and then fixed his gaze on that one thin silver iron book.

  The silver iron books surface is inscribed with four words: "Time and Space Secret Manual"

  This time, Zhang Ruochen was prepared, circulating his true energy throughout his body, mobilizing all his strength, and turning to the first page of the Time and Space Secret Classic.

  "So easy"

  The space-time secret book is very easy to read, without any effort at all.

  Zhang Ruochen shook his head in disappointment and stopped circulating the true energy, picking up the Time-Space Secret Classic and holding it carefully in his hands.

  The first page of the Time and Space Secret Book records not a cultivation secret book, but the notes of the previous owner of the Time and Space Crystal, "Xu Mi Sheng Seng".

  After Zhang Ruochen finished reading the records of Xu Mies holy monk, he finally understood everything.

  "It turns out that the Divine Martial Seal I activated is actually the Space-Time Divine Martial Seal. According to what Mustard Saint Monk said, not even one in a hundred million people can activate the Space-Time Divine Martial Seal. From ancient times to now, there have only been two people who could do it, and counting me, that makes three."

  "Xu Mi Sheng Seng was the second person to unlock the Space-Time Divine Seal, but according to the records on the Space-Time Secret Classics, he had already died over a million years ago. Over a million years ago, that was already the Middle Ages, too far away from now."

  Zhang Ruochen is currently in the inner space of the Time and Space Crystal.

  The flow of time in the inner space is completely different from the outside world. Practicing for three days in the inner space, only one day has passed in the outside world.

  Zhang Ruochen was overjoyed and exclaimed, "In just three days of cultivation inside, only one day has passed outside. Isnt that equivalent to having three times more cultivation time than others? Its truly wonderful."

  Zhang Ruochen wanted to turn to the second page of the Time and Space Secret Book, but no matter what method he used, he couldnt turn it over.

  "Unable to open."

  Zhang Ruochen had an urge to slam the Space-Time Secret Book on the ground, but suddenly, he saw a line of small words at the bottom of the first page.

  "When cultivation reaches the Small Boundary of the Yellow Extreme, one can infuse true energy into the painting scroll and open it."

  Zhang Ruochens gaze fell on the painting again, and he speculated that it must have recorded some kind of mysterious technique, perhaps related to cultivating time and space.

  "Strive to cultivate and strive to break through to the minor extreme position as soon as possible. Lets see what secrets are hidden in the painting."

  "Small ultimate" is the fourth small boundary of Huangji border, and then its Zhongji position, Daji position, and Dacheng.

  Zhang Ruochens stomach growled with hunger, so he immediately temporarily exited from the inner space of the Time and Space Crystal and returned to his room.

  He clutched the Time-Space Crystal tightly in his hand, and with this crystal, he had a greater grasp of reaching the late stage of the Yellow Extreme Realm within three months.

  Zhang Ruochen, Lin Fei and servant girl Yuner sat together eating breakfast.

  All they had was plain rice and steamed buns, without any meat in sight.

  For warriors, the physical strength consumed is much greater than that of ordinary people, so eating becomes particularly important.

  Those princes and dukes who had activated the Divine Martial Imprint ate "Blood Pellets" made from the blood of ferocious beasts every day, and no longer consumed ordinary food.

  Taking a Blood Pill can replenish a whole days worth of physical exhaustion, even if one practices martial arts or swordsmanship for an entire day, they wont feel hungry.

  Moreover, taking Blood Dan also enhances blood energy, strengthens the martial body, and increases physical strength.

  If it were Zhang Ruochen, eating plain rice and steamed buns would be far from enough to sustain his bodys consumption, even if he ate eight meals a day.

  "Dust, youve already activated the Divine Martial Mark, so you cant eat ordinary food anymore. Take these ten Blood Pellets for now, and if theyre not enough, Mother will think of another way." Lin Fei took out a jade bottle and handed it to Zhang Ruocheng.

  Zhang Ruochen was gnawing on a steamed bun, never thinking that Lin Fei could actually take out ten Blood Dans. He asked in puzzlement: "Mother, five silver coins can only buy one Blood Dan, so ten Blood Dans would be fifty silver coins, where did you get so much money?"

  Lin Fei smiled and said, "Mother always has a way."

  The maid Yuner stood behind Lin Fei and said, "Your Highness sold the favorite hairpin gold pin to exchange for ten blood dan in Dan City."

  Lin Fei gently glared at Yuner, as if blaming her for being too talkative. Then she continued: "Chener, dont think too much, as long as you can cultivate into a true warrior, Mother will support your cultivation even if she has to sell all the accessories."

  Zhang Ruochens heart was deeply moved, he tightly grasped the jade bottle in his hand, biting his lip, wanting to tell Lin Fei that he had already become a true warrior.

  No, cant do that.

  It only took one night to open up the air pool and complete the washing of the meridians, it was really too fast. If the news accidentally leaked out, it would definitely be transmitted to the ears of other princes and queens. At that time, it would harm not only oneself but also Consort Lin.

  He is still too weak and small now, needs more powerful strength.