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

Chapter 11 Cleansing the Marrow and Refining the Essence, A Thousand-Year-Old Earth Core Flame? A Weakened Version of the Azure Lotus Earth Core Flame!
[In the fifth month, for killing Liu Mubai, you were expelled from the Northern Spirit Academy. The Lord of the Liu Domain was furious and issued a kill order against you throughout the entire Northern Spirit Realm, thus beginning your life as a fugitive.]

[In the sixth month, relying on the resources of the Blood Slaughter Mercenary Group and the young master of the Liu family, your cultivation broke through to the late stage of the Spirit Wheel Realm, and you became a first-level alchemist. Using the poisons you refined, you turned the tables on your pursuers and escaped into the forbidden area of ​​the Northern Spirit Realm—the Black Abyss.]

[In the seventh month, guided by the Nine Nether Sparrow's hiding place map, you arrived at a region infested with Spirit-Devouring Bees and stopped there, not venturing any further. In a mysterious cave, you obtained the inheritance of the Spirit Insect race.]

Based on your memories from your past life, you know that this prodigy of the spirit insect clan most likely came to track down the Nine Nether Sparrow, but he was caught off guard and ended up benefiting you.

After obtaining the inheritance of the Spirit Insect Clan, you quickly left the Black Abyss, without even considering capturing the Nine Nether Sparrow, even though it was a young sparrow that had failed to break through to the Supreme Realm.

[In the eighth month, you began studying the art of spirit insects. Relying on your considerable soul talent, you quickly absorbed what you learned. Subsequently, you returned to the Black Abyss, mastered the Soul-Devouring Bee Swarm, and officially became a Level One Spirit Insect Master!]

[In the ninth month, the Lord of the Willow Domain, seeking revenge for the murder of his son, personally led a group to the Black Abyss to hunt you down. Relying on tens of thousands of Soul-Devouring Bees, you relentlessly wore down this late-stage Divine Soul Realm expert, achieving instant fame!]

With this battle, your name resounded throughout the Northern Spirit Realm, and the world revered you as the "Bee Queen." For a time, all the major powers in the Northern Spirit Realm avoided you.

[In the fifth year, Liu Jingshan, the patriarch of the Liu Domain, emerged from seclusion and learned of his grandson's death. Having already reached the Fusion Realm, he joined forces with several Divine Soul Realm cultivators to hunt you down. You were no match for them, and severely injured, you fled into the depths of the Black Abyss, your whereabouts unknown.]

[In the sixth year, you have nurtured the Soul-Devouring Bee Queen into the Soul-Devouring Bee Emperor, a unique individual comparable to a Fusion Realm expert. You have officially become a Level 3 Spirit Insect Master!]

[Subsequently, you led the Soul-Devouring Bee Queen and a swarm of 100,000 Soul-Devouring Bees to attack the Willow Domain. Liu Jingshan was no match for them, and the Liu family was subsequently destroyed. The Northern Spirit Realm was shaken, and the title of "Bee Queen" was truly well-deserved!]

In the seventh year, relying on the resources of the Liu family, you cultivated to the late stage of the Divine Soul Realm, but could not advance any further. You decided to leave the Northern Spirit Realm and travel to other regions of the Hundred Spirits Continent to seek opportunities for further advancement...

[In the eighth year, relying on your dual identities as a spirit insect master and alchemist, you became a disciple of the ninth prince of the Hundred Spirits King, serving as his retainer, thus gaining access to abundant resources and breaking through to the Fusion Heaven Realm.]

[In the ninth year, the Ninth Prince and the Eighth Prince began a territorial struggle. Relying on your status as a Level 4 Spirit Insect Master, you commanded 200,000 Spirit-Devouring Bees, enough to rival a Transcendent Realm expert, and helped them capture three cities. As a reward from the Ninth Prince, you obtained a low-grade divine-level attack spirit technique—Heavenly Dragon Flame Finger!]

[In the tenth year, you devoted yourself to the study of spirit insects. Relying on the abundant resources bestowed upon you by the Ninth Prince, you broke through to the fifth level of spirit insect master, enough to rival a Tongtian Realm expert. You became the Ninth Prince's top spirit insect master, highly valued by him, and began your attempt to break through to the first level of the Supreme Lesser Three Tribulations: the Physical Body Tribulation.]

[Because you previously consumed a large number of pills and spiritual items, your foundation is unstable, making it difficult to succeed in your physical transformation. Upon learning of this, the Ninth Prince sent you a bottle of Earth Core Flame Elixir to help stabilize your foundation.]

【Earth Core Flame Elixir: A rare fire-attribute elixir in the vast world, produced from the depths of the earth's core magma and refined over thousands of years. It contains pure earth fire power, which can burn away impurities in the body, cleanse the marrow and strengthen the body, and help cultivators break through the shackles of the physical body.】

Even low-level alchemists who consume this product will experience a significant increase in their fire attribute affinity, greatly enhancing their fire control precision and dramatically increasing their success rate in refining high-grade pills. It is truly a rare and precious item.

[After consuming the Earth Core Flame Elixir, which cleansed your body of impurities, purified your meridians and marrow, and underwent three years of seclusion, you finally succeeded in overcoming the physical barrier!]

[This simulation ends——]

You can choose one of the following three items.

【1. Mustard Seed Bracelet (Low-grade Spiritual Artifact)】

Second, Heavenly Dragon Flame Finger (Divine-level Low-grade Attack Technique)

[Three, Earth Core Flame Elixir]

Lu Yu stared at the final simulation result displayed on the light screen, a hint of self-satisfaction flashing in his eyes: "To have reached the Lesser Three Tribulations of the Supreme Realm as a mere stable boy, such an achievement is not in vain for this plan."

He gently stroked his chin, thinking thoughtfully, "But while it's okay to play like this in a simulation, there's no need to be so reckless in reality."

"I already have a storage ring, so I don't need the mustard seed bracelet." "As for the Heavenly Dragon Flame Finger and the Earth Core Flame Elixir, I will naturally choose the Earth Core Flame Elixir, which can increase fire attribute affinity."

"According to the simulator's classification, the Xuan-rank advanced technique, the Flame Manipulation Technique, belongs to the upper-grade spirit level. The lower-grade divine level attack technique, when converted to the cultivation level of the Dou Qi Continent, should be equivalent to the lower-grade earth level Dou Technique. In terms of value, it is far from comparable to the Earth Core Flame Spirit Liquid."

"In that case, there's nothing to hesitate about."

With a thought, Lu Yu chose the third option. Immediately, a blue light flashed, and a delicate little bottle carved from cold jade appeared in his palm.

The bottle feels cool to the touch, yet one can vaguely sense the intense heat emanating from within.

"This is the Earth Core Flame Elixir..." He carefully uncorked the bottle, and a wisp of crimson mist immediately rose up, condensing into a lotus shape in the air. The mere release of this aura caused the temperature in the room to rise sharply, and the candle flame on the table leaped three feet higher.

"Such pure fire elemental energy..."

A look of surprise flashed in Lu Yu's eyes, and then he put a drop of crimson liquid, as red as magma, into his mouth without hesitation.

"boom--"

A surge of violent fire energy exploded within his body, causing Lu Yu's meridians to feel as if they were being scorched by flames, his skin turning crimson, like a boiled shrimp. He endured the excruciating pain, circulating the Great Floating Pagoda Technique to guide the energy through his meridians.

"laugh--"

The impurities accumulated in his body were completely burned away by the Earth Core Flame Elixir, turning into black smoke that was expelled through his pores. Lu Yu's bones emitted crisp cracking sounds, and his aura surged dramatically!
Late-stage Two-Star Dou Shi!

Peak Two-Star Dou Shi!

Samsung Fighter!

Four-star Dou Shi!

"call--"

Lu Yu suddenly opened his eyes, his pupils flashing crimson. A condensed white mist shot out from his mouth, instantly melting a fist-sized hole in the bluestone floor three zhang away.

Looking inward at the dantian, it was discovered that the residual Earth Core Flame Spirit Liquid energy in the body had not dissipated, but instead condensed into a cluster of leaping crimson flames in the dantian!

This is the millennia-old subterranean flame!

Looking at the cluster of crimson flames within his dantian, Lu Yu was first taken aback, then suddenly realized:
"So that's how it is. This is the secret of tempering the body with the Earth Core Flame Spirit Liquid. This spirit liquid actually contains a trace of the millennium Earth Core Flame. Although it can't compare to the Azure Lotus Earth Core Flame, which is a lava fire that has been compressed and tempered for a thousand years, it can still be considered a weakened version of the strange fire."

"If I absorb a different kind of fire, wouldn't that remove impurities from my body and strengthen my foundation?"

"Absorbing a different kind of fire would greatly increase one's affinity with fire, wouldn't it?"

"I just don't know, what rank on the Strange Flame Ranking is my Thousand-Year Earth Core Flame equivalent to?"

With a thought, a wisp of crimson flame flickered on Lu Yu's face, reflecting his thoughtful expression.

(End of this chapter)