Theories

Seo Eun-hyun is a Heart Demon

Heart Demons are beings formed by "Desires". Seo Eun-hyun is theorised to be the Ender of Desire.

What is the Head Realm?

The Head Realm is the skull of the First Radiance Supreme Deity.

• Hyeon Rang and Hong Fan(assumed to be Black Snake) look almost exactly the same.
• Hyeon Rang also resembles Song Jin. Song Jin's skull structure is the same as that of the Head Realm.
• Cheon Woon, the Heavenly Venerable of Time, call Hyeon Rang a "substitute" for fate.
• This further implies the Head Realm and the Akashic Record are under the control of the Radiance Supreme Diety. This is further supported by the fact only Immortal Arts permitted by the Radiance Supreme Diety are allowed to function in the Head Realm.
• It is also possible the Akashic Records are the anchor for Regression.

Ender Pill Theory

"All dreamworlds are actually equally as real as Mt Sumeru" or "Mt Sumeru is a dream"

Proof:

1. Weak speculative foreshadowing (Penglai Island arc): some time after they awaken in Penglai and realise it's a dream, SEH comforts one of his friends by telling them to "treat both Penglai and Mt Sumeru as a dream". However, SEH treats both as real. This could foreshadow how everything in Mt Sumeru could be a dream, and also links to how dreams may become reality in Mt Sumeru.
2. The theme/fact that Seo Hweol's world was a dream in the dream of Head Realm, which could mirror the dream of Head Realm existing in the dream of Mt Sumeru.

Who is the Future King?

Hyeon Mu is arguably a fragment of the Future King.

• Hyeon Mu states that all fate that is given must be returned before setting forth to hunt Kim Young-hoon. This implies she is the one who gave the Enders their Fate.
• Building on this, we also learn that Hyeon Mu was given her position by a greater being, possibly the Future King, meaning that she would also have to return to him.
• Ender Fates are presumed to originate from the Future King.
• Hyeon Mu's true body is a Three Great Ultimates formed by black snakes, similar to the [Black Snake] of Radiance.
• Netherworld as [She] explicitly said the "North" is their most powerful enemy.

Heart Path Lifespans

Those who look deeply into the Heart pursue a different path from Immortal Cultivation. Though they may be as powerful, they live significantly shorter lives that Heaven/Earth Path cultivators. However, much about these lifespans are not known.

Known information

• Seo Eun-hyun said the Second Stage of Manifestation gave 49 years.
• Seo Eun-hyun said the Third Stage of Manifestation gave 343 years.
• Kim Young-hoon said the First Step Before the Throne gave at least 10,000 years.
• After reaching Second Step Before the Throne Seo Eun-hyun's lifespan reached millions of years. Though this information is vague, as he had also cultivated up to the Integration stage in Heaven and Earth Paths.

Note that these lifespan increases only apply to the Human Race. Lifespan increases in all three Paths always scale according to the race's natural lifespan. Dragons with long lives will always receive more lifespan than flowers for advancing in cultivation.

Theory

This theory is based on the exponential increase between Second and Third Stages of Manifestation, in that 7 x 7 = 49 while 7 x 7 x 7 = 343. Extrapolating from this trend, we will get the following:

Explanation

First Step Before the Throne is unique in that the pattern changed. While First (7^1), Second (7^2), and Third stages Manifestation (7^3) each only increase by an exponent of one, First Step Before the Throne (7^5) increased by an exponent of two. The reason for this is twofold:

• 7^4 would only result in 2,401, thus contradicting Kim Young-hoon's statement.
• 7^5 = 16,807 does indeed corroborate the statement, "At least 10,000 years". But it could also reference the fact that First Step Before the Throne is the equivalent of both the Four-Axis and Integration stages in Immortal Cultivation.

Since Second Step Before the Throne corresponds to both the Star Shattering and Sacred Vessel stages, Second Step should likewise be 7^7, not 7^6.

Meanwhile, Third Step Before the Throne only corresponds to the Entering Nirvana stage, so it should be 7^8. A potential corroborating evidence for this is that 7^8 = 5,764,801 years, and in Q&A 5, Tremendous stated that, on average, cultivators take 5 million years to reach True Immortal.[1] Since lifespan is assigned by the heavens, this could be on purpose.

Confirmed Theories

The Setting of the Regression Point

Seo Eun-hyun's regression point seems to fix under the following conditions:

• He is outside of the Head Realm and in the Interdimensional Void.
• He has just witnessed an Ender realise their fate.

Hong Fan = Black Snake = Light

Theory confirmed in chapter 652.

Seo Ran is Seo Hweol's main body

• Seo Hweol is strangely insistent in Seo Ran's death, even leaving a four-fold plan to kill Seo Ran in the Head Realm. From Seo Li's experience, we know that the death of the "main body" causes the "main body" to reset. Also, the 'clone' cannot directly kill the main body. This implies Seo Ran's death would allow Seo Hweol to switch to a "main body" under his control.
• After being blinded by the [Chief Judge of the Netherworld], Seo Hweol states he must reach his main body to regain his vision. After this, he make desparate attempts to acquire Seo Ran's blood and/or soul. Since having those items would allow him to access Seo Ran's authority, which would also include regaining his vision, implying that Seo Ran is indeed Seo Hweol's main body.
• In the Dream World, Seo Ran is always among the first to wake up, usually gaining awareness before Seo Eun-hyun. This implies a large number of being cherish him. It is possible that he gains awareness through Seo Hweol's Tainted Soul Filling the Heavens, which causes the target to 'adore' the caster.

Hong Fan is Gu Ju

Seven Enders, Seven Heavenly Kings, Seven Emotions

Tae Yeol-jeon's Manifestation possessed seven moves which represent the seven Heavenly Kings of the Buddhist Family Methods. These seven moves seem to represent the Enders. The Seven Brilliances Kings are more deeply connected with the seven Enders, more clearly than the Ender's Tale. Their connection was confirmed when the Sacred Master of Nether Ghost Realm, Yu Oh, called Seo Eun-hyun a Heavenly King designate. The relations are as followed:

• Kim Young-hoon: The Golden Body Heavenly King, symbolizing the instant.
• Jeon Myeong-hoon: The Red Pearl Extinguishing Heavenly King, symbolizing the cycle.
• Kang Min-hee: The Lapis Lazuli Protecting Heavenly King, symbolizing protection
• Oh Hyun-seok: The Silver Basket Heavenly King, symbolizing infinity.
• Kim Yeon: The Tridacna Vast Cold Heavenly King, symbolizing unity.
• Oh Hye-seo: The Agate Hatred Heavenly King, symbolizing pain.
• Seo Eun-hyun: The Obsidian Devil Heavenly King, symbolizing filth.

Disproven Theories

Advancement Ritual for True Immortal

This is disproven in Entering Nirvana (개열/開涅) Advancement. While the part about killing oneself, to face "death", is true, the part about desecrating fate is false, as one must actually die, and then leave one's physical body behind to advance.

Seo Eun-hyun's fate

Various early theories regarding regression not being an Ender ability, trading fates with Hong Fan, and Hong Fan being a RDS were disproven in later chapters (652, 674).

Eun-hyun is Guju

Assumed out of flashes of memories featuring Hong Fan. Disproven later.

True Meaning of Being a Heavenly Venerable

Theory posited they must be of the Heart Tribe and achieve Manifestation.

Regression is a Trap

Disproven as seen with deeper explanations related to the mechanics of the Regression Point and Ender Fate realization.