While the player is in Battle Through the Heavens, the system is in The Great Ruler.

Chapter 79 Choice
"hiss……"

"Oh no, my simulation has really stumbled upon a tremendous opportunity..."

"The Celestial Supreme Inheritance left behind by the Heart Demon Thunder Emperor, who originated from the Ancient Thunder Palace..."

"We were incredibly lucky with this simulation..."

A look of surprise crossed Lu Yu's face, followed by a look of delight.

As we all know, in the ancient times of this vast world, it was an extremely glorious and brilliant era, with peerless experts shining like stars.

The peerless goddess Luo fought two against one, killing one and severely wounding the eighth and ninth ranked demon emperors of the extraterrestrial evil race; the patriarch of the ancient Floating Pagoda clan single-handedly slaughtered dozens of demon emperors, using their corpses to forge the mighty Eight-Part Floating Pagoda; the Heavenly Array Elder, who rose from a rogue cultivator to become a Grandmaster of Saint-grade Spirit Arrays, set up the Sacred Abyss Array...

It was truly a time when heroes rose up and geniuses vied for glory! Among them, the most dazzling were none other than the nine supreme beings—the Nine Ancient Emperors!
Each and every one of them is an unparalleled powerhouse, surpassing ordinary holy items. In particular, the Immortal Emperor, the head of the Nine Emperors, has successfully left his mark on the Heavenly Ranking, stepping into the supreme realm of half-step ruler!
"Based on the clues in the simulation, the Heart Demon Thunder Emperor was able to be guided by the Ancient Thunder Emperor, so he must either be his disciple or one of his capable subordinates. Among the Nine Ancient Emperors, the Heavenly Emperor rose to fame the latest, and he didn't even have a single Heavenly Sovereign under his command..."

"Compared to the Heavenly Emperor, that Thunder Emperor is clearly a cut above, at least he taught someone like the Heart Demon Thunder Emperor..."

"That Three Yang Thunder Technique is indeed tempting; in terms of value, it's probably not much different from the Strange Fire Spirit Vein Technique I possess..."

"Unfortunately, this kind of secret technique that can reverse the attributes of spiritual objects probably has an extremely high threshold, requiring at least the Supreme Realm to perform, which is not something I can use right now..."

"As for the Thunderous Heaven-Shaking Palm and the Profound Thunder Body Forging Technique, they are merely high-level Earth-rank cultivation techniques and combat skills. I can find similar inheritances on the Dou Qi Continent, so they are not particularly rare..."

"As for the other two options..."

Lu Yu's gaze sharpened slightly, first landing on the first option, then he gently shook his head before shifting his gaze to the second option.

"The lotus seeds of the Heavenly Spirit Lotus are used to stabilize spiritual power and solidify the foundation. However, my current realm is very stable, and there is no sign of my battle qi becoming weak, so these lotus seeds are not of any use to me for the time being..."

"As for the Netherworld Demonic Flame..."

Lu Yu's eyes narrowed again, and in an instant he understood the deeper meaning behind the simulation.

He needs to cultivate the Heavenly Fire Forging God Technique, and to cultivate this technique, he needs a strange fire to temper his soul.

The Netherworld Demon Lightning is an extremely rare type of soul-type lightning in the vast world. The Netherworld Demon Fire that it transforms into must also contain its unique soul characteristics and have a strong destructive power against the soul.

If one uses the Netherworld Demon Fire to temper one's soul, when one eventually reaches the realm of fire transformation, one's soul will be imbued with its characteristics.

At that point, it would be equivalent to having two different flames empowering you. Even without cultivating any soul skills, you would likely be invincible in soul battles against opponents of the same realm.

"Just choose it."

"But not here, we need to find a secluded and quiet place..."

Lu Yu had a sudden thought, and immediately stood up, pushed open the door, and found the courtyard quiet.

Little Fairy Doctor remained secluded in her room, diligently cultivating, while Zi Yan sat listlessly on the stone steps, happily munching on a spiritual herb.

"Huh? You finally came out!"

Zi Yan's eyes lit up, and she swallowed the elixir in a few gulps, then hopped over to him.

Lu Yu gently patted her head and said softly, "Zi Yan, would you take me to a secluded spot in the back mountain of the inner courtyard? I need to go into seclusion and will need your help to protect me."

Zi Yan pouted and said, "Another seclusion..."

But then she patted her chest and assured them, "Don't worry! With me here, I guarantee not even an ant can crawl in!"

After saying that, she grabbed Lu Yu's sleeve and ran outside, saying as she ran, "Come on, come on, I found a good place last time, I guarantee no one will find us..."

Upon hearing this, Lu Yu chuckled and then followed Zi Yan out of the courtyard. Before long, the two arrived deep within the back mountains of Canaan Academy. Passing through a dense, ancient forest, a hidden cave suddenly appeared before them. The entrance was half-concealed by hanging vines, making it extremely difficult to spot without close inspection.

“That’s it!”

Zi Yan parted the vines and explained proudly, "Last time I found a thousand-year-old spiritual ginseng here, and I just remembered this place."

The cave was dry and well-ventilated, and although not large, it was spacious enough for one person to cultivate. A faint medicinal fragrance lingered on the rock walls, presumably left by Zi Yan after her previous feast.

Lu Yu nodded in satisfaction and said, "It is indeed a good place."

He then took out several bottles of pills and handed them to Zi Yan, instructing her, "These pills should last you a while. Would you mind guarding the cave entrance for me?"

Zi Yan snatched the jade bottle, her eyes crinkling into crescent moons with laughter, and said cheerfully, "Leave it to me!"

After saying that, he skipped and ran out of the cave.

After Zi Yan left,

Lu Yu sat cross-legged in the center of the cave. He raised his hand to set up a cyan-red energy barrier, then took a deep breath and made a slight mental movement.

"Om-"

The void suddenly trembled, and a ball of dark black flame appeared out of thin air, with eerie lightning flashing continuously at its core, each pulse accompanied by a piercing thunderclap.

Lu Yu felt a violent tremor in his mind, as if his soul was being pierced by thousands of lightning needles. The Great Floating Pagoda Technique within his body activated spontaneously, and a crystalline phantom of a floating pagoda appeared above his head, barely managing to withstand the soul impact containing eerie thunderous sounds.

"What a magnificent Netherworld Demon Flame!"

Lu Yu's eyes flashed with a sharp light, and his right hand, wrapped in cyan-red flames, fiercely grabbed at the fire seed.

"Crack-"

The moment the two flames clashed, a deafening thunderclap erupted. Lu Yu's left hand rapidly formed hand seals, countless ancient runes intertwining in the void, transforming into a colossal black python coiled around him with dark light. As the Floating Pagoda trembled violently, the python instantly coiled around it!

"The Serpent's Sealing Spell!"

The seal containing the power of the Floating Pagoda crashed down, and the unruly demonic fire immediately weakened, its violent aura being forcibly suppressed to the Dou Ling level.

"I already have a Core Flame within me. If I want to refine a second Strange Flame, I need to temporarily hide it. Otherwise, the two Strange Flames will clash within me, and even a Dou Zun expert wouldn't be able to suppress them..."

With a thought, Lu Yu activated the Great Floating Pagoda Technique within his body, instantly drawing the weakened Earth Core Flame into the Floating Pagoda. The ancient pagoda shone with a brilliant light, completely isolating the strange fire's aura.

Although the pagoda is not yet fully solidified, it is more than enough to temporarily contain the weakened Earth Core Flame.

Immediately, Lu Yu took out a pill bottle, and a blood-red pill appeared in his palm.

It was indeed a Grade 5 Blood Lotus Pill.

He swallowed the pill in one gulp. The moment it entered his mouth, his whole body trembled violently. Countless blood beads seeped out from his pores and instantly congealed into blood-red keratin, covering his entire body completely.

"it's time……"

Taking a deep breath, Lu Yu swallowed the Netherworld Heart Demon Fire Seed without hesitation. Instantly, a scorching torrent surged and raged through his meridians.

He endured the excruciating pain and took out another jade box, which contained the Ice Spirit Cold Spring.

As the cold spring water entered his stomach, the scorching heat was instantly suppressed, allowing him to breathe a sigh of relief. Immediately afterward, the fighting spirit within his body surged towards the fire seed like a tidal wave.

Refining, officially begins!
(End of this chapter)