(Befall - Shang Wanjie and HOYO-Mix)

https://youtu.be/dxLsI5AKLpE

Shadow: Led by the mysterious Otto Apocalypse Schicksal is one of the two organizations alongside its former branch Anti-Entropy that lead the fight against the cataclysmic Honkai. But whereas Anti-Entropy is mainly stationed in North America and uses mechs and whatnots, Schicksal's influence goes beyond their homeland and deploys Valkyries, female warriors who are known for the incredible battle prowess and very high resistance to Honkai energy. 

Randy: But like any fictional peacekeeping, worldwide organization, Schicksal has been hiding dark secrets, like experimenting on humans. You see, Otto had made plans to resurrect his someone he loved, Kallen Kaslana, who was slain 500 years ago. Some of these experiments were held in Siberia, Russia in the form of Babylon Labs and one of those experimented on was an orphaned girl named Sirin.

Adam: Sirin lived a pretty normal life with her mother in Belarus, until things went oh so wrong. See, the Labs were created in the 20th century and they released a lot of Honkai radiation that infected neighboring villages. Many have died including Sirin's mother, but she and the surviving ones developed high Honkai resistances. They were then taken in by doctors who claim to have a cure but in reality decided to use them as lab rats to create Stigmatas, which serves as a defense against the Honkai and that they should feel grateful for being able to die for such a cause. Otherwise, they were treated like filth.

Shadow: Many of them died during the experiments, but Sirin has survived years of abuse and inhuman treatment at their hands. Sadly, Bella and her friends were not as fortunate. This would continue one fateful night on February 1, 2000. Sirin escaped and murdered all the 322 scientists there. Fortunately, Schicksal Valkyries Theresa Apocalypse and Patricia Highsmith were dispatched to the Babylon Lab and rescued the remaining survivors.

Adam: Unfortunately, years of experimentations has convinced Sirin to take revenge against Schicksal and all of humanity itself. After injuring Patricia and escaping the Babylon Tower, Sirin had become a Herrscher, a human that's corrupted and imbued by the Honkai energy and their sole mission to annihilate whole civilizations and waged war with humanity, instigating the one of the most devastating events in the Current Era; the Second Eruption.

Sirin

Herrscher physiology

Herrscher Core

Core of the Void

Extrasensory Perception

Time Manipulation

Gravity Manipulation

Flight

Telekinesis

Battlefield Removal

Power Absorption and Nullification

Pocket Reality Manipulation

Black Hole Creation

Portal Creation

Regeneration

Abstract Existence & Nonexistent Physiology 

Regeneration Negation

Life Manipulation

Death Manipulation (Gem of Death)

Deconstruction

Fire Manipulation (Gem of Haste)

Ice Manipulation

Wind Manipulation (via Gem of Serenity)

Lightning Manipulation (via Gem of Conquest)

Summoning (Can summon Templar-Class Honkai beasts via portals)

Resistance to Corruption Biological Manipulation, Power Absorption, Lightning Manipulation, Fire Manipulation, Gravity Manipulation, Energy Manipulation, Corrosion Inducement, Life Manipulation, Matter Manipulation, Quantum Manipulation, Information Manipulation, Higher-Dimensional Manipulation, Chaos Manipulation, BFR, Existence Erasure, Fate Manipulation, Conceptual Manipulation (Type 2), Madness Manipulation, Soul Manipulation, Perception Manipulation, Law Manipulation, Reality Warping, Spatial Manipulation, Physics Manipulation, Transmutation, Time Stop/Reset, Death Manipulation, Deconstruction, Regeneration Negation, Sleep Manipulation, Memory Manipulation, Illusion Creation, Telepathy, Soul Manipulation, Mind Manipulation and Dream Manipulation

Reality Distortion Field

Imaginary Space

Imaginary Barrier

Gem of Serenity

Gem of Death

Gem of Desire

Gem of Haste

Adam: Herrschers are capable of bending the laws of physics and reality to their whim and control certain concepts of the universe. As the Herrscher of the Void, Sirin is capable of controlling gravity, creating portals and black holes out of thin air, making pocket dimensions to travel or escape to and stop time with Time Fracture. She also possesses flight, illusions and the ability to create weapons made out of Honkai energy.

Randy: She can even possess other people and can summon Honkai beasts with her portals. And as the Honkai adapts, do does a Herrscher. Oh and unless you destroy a Herrscher's Core, they'll come back or take on a new vessel.

Popup: While Sirin was in possession of Kiana's body in the main story, keep in mind that Kiana (K-423) was created with the purpose of resurrecting Sirin and has proven to be able to use her powers with Kiana's body such as in Chapters 7-9 and the Moon Shadow manga.

Shadow: But that wasn't enough. After encountering the Will of Honkai, aka God, Sirin was given 4 Gems, which are lesser Herrscher Cores but still potent, to aid in her quest. The Gem of Serenity gives her insane regeneration and control death itself, Gems of Haste and Conquest command fire and lightning respectively and the Gem of Desire has power over wind. Sirin also has her Imaginary Space and Imaginary Barrier.

Randy: The Imaginary Space exists outside of the main universe and able to traverse into other worlds which Sirin can pull her targets into. She is able to create objects into "imaginary" that can phase through "real" things, thus turning anything Sirin wants intangible and vice versa. Meaning she can ignore conventional durability.

Adam: Likewise, the Imaginary Barrier can defend against higher-dimensional attacks. And then there's the Reality Distortion Field which can change properties of space-time. This can range from annihilating at the atomic level, create parallels worlds, regenerate from near death, causing supernatural phenomenas and reverse time.

Feats

Ignited the Second and Fourth Eruptions

Considered to be a powerful threat to the point Schicksal and Anti-Entropy, who're at war with each other years ago, formed an alliance against her

Defeated Welt Yang, Raiden Mei, Theresa Apocalypse, and Bronya Zaychik

Held her own against Himeko Murata who donned the Vermillion Knight: Eclipse, a Godsbane-class Battlesuit and had the Gem of Haste implanted on it

Able to resist Fenghuang Down

Survived Fu Hua's Blade of Taixuan

Stole the Gem of Conquest from Mei

Stated in the visual novel to be capable of creating solar systems and tanking supernovas

Massacred 322 Babylon Labs scientists

Destroyed St. Freya instantly

Will take over Kiana's body if she uses too much Herrscher powers (Chapter 11 EX game over)

Resisted Oath of Judah's Honkai-nullifying chains while in Kiana's body

Shadow: Sirin is one of the deadliest Herrschers the Current Era has ever encountered. She's overpowered Raiden Mei and stole the Gem of Conquest back, destroyed multiple Anti-Entropy mechs and hurled giant pillars down to Earth from the moon. She even matched Welt Yang, the Herrscher of Reason and sovereign of Anti-Entropy, in a fight and that guy has the Star of Eden which generates 11D gravity that can affect all dimensions and destroy two higher dimensional realms.

Randy: Granted she was nearly killed had Otto not intervened, but Sirin had been able to resist his black holes. And Sirin is tough enough to survive Phoenix form Fu Hua's Blade of Taixuan and even able to see through Fenghuang Down, which traps its target in false realities and dreams. And in Kiana's body, Sirin is able to resist Theresa's Divine Key Oath of Judah, which nullifies Honkai powers at the metaphysics level. And in the visual novel, she and Welt are stated to be capable of creating solar systems with their Honkai energy.

Popup: Bronya Zaychik, who is Welt Yang's successor as the Herrscher of Reason who Sirin fought, is able to traverse the Sea of Quanta, which is infinite in size and thus puts her at infinite speeds.

Adam: While it's unclear if every Herrscher is comparable to each other, especially with stronger ones not seen in the Previous Era like Flamescion, Rimestar, Human: Ego, Origin, etc., all Herrschers draw their power and energy from the Imaginary Tree, a infinite cosmological structure that forms the Honkai multiverse. It exists beyond space and time and has been stated to be both transfinite in number and holds "absolute infinite power". To paint a picture of how complex it is, its counterpart, the Sea of Quanta, is 11D and contains infinite bubbles universes and more. Yet the Imaginary Tree is much more layered than that.

Randy: Holy hell.

Weaknesses

Had been defeated multiple times;

Defeated by Fu Hua while possessing Kiana's body

Defeated by Kiana for control over her body (Chapter 25)

Defeated by Siegfried

Prone to anger

Himeko used a serum meant for her on Sirin to suppress her influence over Kiana (Final Lesson)

Has a habit of calling people "cheaters" when overwhelmed

Unable to escape Fenghuang Down on her own

Vulnerable to Divine Keys, which are specifically designed to battle Herrschers and are even made out of Herrscher Cores from the Previous Era

Shadow: And yet despite Sirin's overwhelming power, she is far from invincible. She has been known to get arrogant and has habit of talking before attempting to finishing them off, which has come back to bite her in the ass multiple times such as when she was nearly killed by Welt in their first bout. And should her Herrscher Core be destroyed, Sirin can be permanently killed.

Popup: In the Second Eruption manga, Theresa's Oath of Judah succeeded in restraining Sirin, only failing to kill her because she was unaware of the Herrscher Core. The reason why it failed after Sirin reawakened is due to the combination of Otto erasing Theresa's memory of Oath of Judah's Zeroth power and Sirin being in Kiana's body, which is much more capable and stronger than Sirin's.

Randy: Also, if the opponents gets the upper hand, Sirin will lose her composure and starts calling them "cheaters". And while she technically won the fight against Himeko, who didn't aim for the killing blow, she was injected with a serum that can neutralize Honkai, thus preventing Sirin from taking over Kiana for a bit at the cost of her life. Sniff, RIP Himeko. And finally, Kiana would confront her for the final time in Chapter 25, defeating her for the right over their body and Sirin vanished for good.

Adam: And yet, Sirin was proud that Kiana is able to her goal of changing the world for the better. In a way, both Kiana and the Herrscher of the Void are the one and the same: Kiana being Sirin's desire to be loved and the Herrscher being her hatred of all humans for what they put her through. But make no mistake, for if humanity does not change their ways, there will be a second Sirin to put them in their place.

Sirin: Humans, your existence is a mistake. War, cheating, jealously, greed. You once made me lose everything. But today, I'll devour everything. Because I am the Honkai!