Imaginary Tree

The stable axis where history flows linearly, growing within the Sea of Quanta.

The Imaginary Tree stands as the central cosmic structure of the Honkai series, serving as the stable framework where all worlds and timelines exist. It is not merely a location but a metaphysical axis where civilizations grow like leaves in chronological order, following the linear rules of history and time. Located within the vast Sea of Quanta, the Tree grows within this chaotic void, and worlds that fail to persist against the Honkai disaster can fall from the Tree into the Sea, becoming unstable "bubble universes" composed only of fragmented time periods. This setting unifies the franchise, connecting titles like Honkai Impact 3rd and Honkai: Star Rail, though connections to Genshin Impact and Tears of Themis as parallel worlds within the same multiverse have not been officially confirmed.

Lore & Background

The cosmology of the Honkai series is defined by the relationship between the Imaginary Tree and the Sea of Quanta. The Tree represents stability, hosting worlds that develop in a strict chronological sequence. In contrast, the Sea of Quanta is an unstable region capable of forming "bubble universes" during natural fluctuations, which lack complete histories and exist only as fragments of specific time periods. This multiverse structure was introduced by Honkai Impact 3rd to connect multiple games into one unified universe.

The dynamic is not adversarial: the Tree grows within the Sea, and worlds that fall victim to the Honkai lose their stability and drop from the Tree into the Sea, transforming into fading bubble universes. This cycle dictates the fate of civilizations across the series, though Genshin Impact and Tears of Themis are not officially confirmed as parallel worlds on the Tree.

Did You Know?

The term 'Honkai' is simply the romanization of the Chinese word 崩坏 (bēnghuài), and there is no confirmed statement that it was chosen to avoid Japanese romanizations for proprietary reasons.
The investment details and the name 'Skye' for Zombiegal Kawaii's angel investment are not part of established Honkai lore or official company history.

Origins and Evolution of the Franchise

The Honkai series originated with FlyMe2theMoon, a paid mobile game for iOS released on September 28, 2011, by the five-person "miHoYo studio" startup team. This initial project introduced Kiana Kaslana as the protagonist and was developed using Cocos2d software and the Box2D physics engine. Following this, the first installment of the Honkai series proper, Zombiegal Kawaii (localised as Houkai Gakuen), launched in December 2012 after receiving a 1 million yuan angel investment from Skye.

Developed using the Unity engine and Maya graphic software, it introduced core companions Mei and Bronya. The franchise continued with Guns Girl Z (Houkai Gakuen 2) on January 26, 2014, which shifted to a free-to-play model while inheriting assets from its predecessor. Under the leadership of producer David Jiang (succeeding founder Cai Haoyu), the series expanded into Honkai Impact 3rd and eventually Honkai: Star Rail in 2023, maintaining connections through shared character designs and the overarching Imaginary Tree cosmology.

The Nature of the Honkai Threat

The "Honkai" is an interdimensional alien force with intelligence that aims to assimilate developed civilizations through any means necessary. Its manifestations include energy waves, infected beasts, and human carriers who exhibit various symptoms. The Honkai can trigger viruses, natural disasters, world wars, or other forms of destruction proportional to the level of civilization in a region. Its highest manifestation is the "Herrschers," beings with powerful specialized abilities and wills. The term itself was coined specifically for the series to refer to this disaster, intentionally avoiding Hepburn (Hōkai) or kana (Houkai) spellings due to proprietary naming considerations. Whenever civilization arises, the Honkai appears, creating a cycle of destruction that forces characters like Kiana, Mei, and Bronya to rebel against these inevitable endings in order to save their worlds.

Character Variants and Narrative Continuity

A defining feature of the Honkai series is the use of "expies" (unofficial term for "isotopes"), where characters like Kiana Kaslana, Mei, and Bronya appear across different games with entirely new personalities, designs, and backgrounds. This technique allows miHoYo to explore different possibilities for a single character while maintaining each work's independent identity. For example, Honkai: Star Rail features well-known characters such as Bronya, Himeko, and Welt Yang, who share visual traits but differ in setting from their predecessors.

This practice extends to Genshin Impact, where the character Raiden Shogun mirrors Raiden Mei, sharing voice actors Juhuahua (Chinese) and Miyuki Sawashiro (Japanese), despite significant personality differences. CEO Cai Haoyu confirmed in 2021 that the Honkai Universe concept was a primary reason for Genshin Impact's development, solidifying these connections across parallel worlds.