Chapter Fifteen: Innate Battle Aura

Caiyao found Li Sibai's hesitant expression quite amusing, and it made her laugh softly.
"Brother Xiaobai, you have many questions, don't you? What is it you want to know? Ask me, and I'll tell you whatever I know."
Li Sibai pondered for a moment, sorted out his thoughts, and then spoke,
"Caiyao, how is it that I've broken through to the fifth level of the Phoenix Origin realm so quickly? I trained arduously for eight years and never managed to surpass the third level. Under your rainbow radiance, I swiftly broke through to the fourth level, and today, with the green aura from that old tree spirit, I've advanced to the fifth. What kind of sorcery is this, so powerful that everything feels almost unreal? Am I dreaming? Hurry and hit me to wake me up." Li Sibai forced a bitter smile, unsure whether he wished this was a dream or not. He felt conflicted in his heart.
Caiyao listened to his questions in silence, organizing her thoughts and considering where to begin with her foolish brother.
"Brother Xiaobai, have you noticed that there are two types of energy within your body?"
Li Sibai's eyes widened. "Yes, yes! How did you know? When you helped me with your rainbow auspices, I felt my pure Yang Mystical Heaven energy, blazing and warm, incredibly comfortable. Today, with the old tree spirit's green aura, my pure Yang energy seemed suppressed, unable to manifest, while a cold, white energy circulated throughout my body. That chill brought another kind of comfort. What is happening?"
Caiyao nodded, her admiration for her brother growing. Although Li Sibai had rescued her by accident, and she later saved him in return, his generosity and steadfast spirit had left a deep impression on her as they traveled together. Now, his careful response revealed a keen mind, and Caiyao silently gave him a thumbs up in her heart.
"That’s right, brother. Your body is unlike others, harboring both red and white energies."
"The red is my Mystical Heaven energy, but what about the white?" Thinking of that cold white energy, Li Sibai felt uneasy, fearing Caiyao might confirm his suspicions.
"Could it be..." The words caught in his throat.
Caiyao, unaware of his inner turmoil, replied firmly, "Yes, Brother Xiaobai, it is the deadly Yin battle energy!"
Li Sibai's mouth dropped open in astonishment. "Ah!"
Though he had suspected as much, he had hoped it wasn't true. Now that Caiyao had confirmed it, the matter was settled.

"How can this be?!"
"How could there be deadly Yin battle energy within me?!"
"Caiyao, are you joking with me? Please don't tease me, I'm really quite timid."
Caiyao hadn’t expected such a dramatic reaction, but upon reflection, it was understandable. Who could remain calm upon discovering they possessed battle energy cultivated by demons and fiends? Such a person would hardly be normal.
"Don't panic, brother. Let me explain."
Li Sibai nodded. His mind was a muddle, lost and desperate for guidance.
Caiyao coughed lightly, then began,
"Brother, let me ask you: among humans, the body is filled with turbid energy, which cannot be cultivated, correct?"
Li Sibai nodded.
"When you cultivate immortality, you absorb the pure energy of nature, extract it through methods like Mystical Heaven Arts to refine true energy, and expel the turbid energy. This cycle repeats until all turbid energy is gone, and then you ascend as an immortal—right?"
Li Sibai replied, "Yes."
"Now, do you know how the demon and fiend races cultivate?"
Li Sibai nodded. "I read about it in the 'Compendium of Strange Beings.' The demon race are essentially ordinary birds and beasts. Their bodies also contain turbid energy, and through chance, they obtain the method to absorb pure energy from nature. However, after absorbing pure energy, they cannot refine it into true energy but instead convert it into battle energy. True energy and battle energy are like Yang and Yin, utterly incompatible."
Caiyao was once again impressed. Despite his recklessness, her brother was surprisingly knowledgeable. Though his cultivation level was not high, he understood the principles well enough.

"Exactly as you said, brother. The two energies, one Yang and one Yin, cannot be reconciled. But have you ever considered, since both are derived from absorbing pure energy, what difference lies between Yang and Yin?"
"This..." Li Sibai hesitated again. He wanted to insist there was a difference, that true energy was the righteous, pure Yang energy, incomparable to the sinister, deadly Yin battle energy. But reflecting on Caiyao's question, from the perspective of cultivation, apart from differing methods, there seemed little distinction; and that left him awkward.
"This... well... there doesn't seem to be much difference..."
His voice grew softer, almost inaudible even to himself, but Caiyao heard him clearly and smiled radiantly.
"Brother, you understood so quickly—I'm truly impressed. Indeed, apart from the cultivation method and the resulting energy, everything else is the same. Both draw upon the pure essence of heaven and earth, merely yielding different sources. Yet, both paths ultimately seek the same goal: you cultivate true energy for immortality, while I cultivate battle energy to become a demon or fiend; in the end, the pursuit is everlasting life."
Li Sibai had grown up on Jade Void Peak of the Mystical Heaven Sword Sect, raised on teachings of the irreconcilable divide between good and evil, the triumph of righteousness over evil, and the duty to vanquish demons. He had always regarded his sect's doctrine as sacred and infallible. Now, listening to Caiyao, he found her words made some sense, leaving him torn and deeply confused.
"But Caiyao, do you know how the battle energy came to be within me?"
"That, I do not know, brother. Let’s ask the old tree spirit; he’s lived longer than I, so he might know." Caiyao chuckled.
Li Sibai wondered aloud, "What happened to him? He seems to have fallen into a deep sleep. Could it be that helping me advance wore him out?"
Caiyao laughed, "Brother, you underestimate him..."