Heng (Nine Sols)

Yi's naive and eccentric younger sister. She has a particularly close bond with Yi.

As one of the few people who can resonate with Fusang, Heng believes in returning to the Tao and that it is natural to coexist and perish with Penglai. She therefore did not cling to life and refused Yi’s proposal to live in New Kunlun. She chose to stay in their hometown and accept the natural end to her life.

Heng (恆) is Yi's younger sister, and a major character from Nine Sols.

Heng is similar in appearance to Yi, due to them being siblings. She shares the same traits of having pointed ears, cream-colored fur and almond-shaped eyes as her brother, but there are still some fundamental differences between them. She tends to show more emotions and facial expressions than her stoic brother, with two pink spots resembling a blush appearing on her cheeks whenever she is excited, embarrassed or annoyed. Heng also seems to have slightly longer eyelashes and is much more petite in appearance, compared to Yi.

Unlike Yi, Heng's eyes have visible, wine-red colored irises. She also has long hair, a small visible mouth and no fur tufts on the sides of her face. Her outfit consists of a black-teal colored Hanfu (Han Chinese traditional clothing) that is a shirt with wide sleeves and a black and long skirt. In some flashbacks, she is also seen holding a flute.

As a child, she was dressed in a teal colored Cheongsam (Chinese-Manchurian traditional clothing), and her hair tufts were noticeably shorter as well.

500 years ago, Heng was born in the Xia Kingdom to two unnamed parents and her older brother Yi. Heng and Yi once shared a really close bond with each other. While Heng didn't really understand science, she always stuck by Yi's side.

No one knew, but Heng had a strong connection with the Fusang Tree/Primordial Roots, being able to hear its voice. She also regularly conversed with the tree when she was a child. But Yi thought she had heard the wrong things with his bias on scientific evidence.

One day during one of Yi's botched development experiment of the Mystic Nymph, Heng was protected by Yi, who sacrificed himself for her. Devastated by Yi's passing, Heng teared up, which prompted the Primordial Roots to have revived Yi from his death.

As they grew older, however, Heng and Yi's philosophies differed more and more especially after their parents passed away - While Heng believed that all Solarians should respect the nature's cycle and accept returning to earth once their lives were over, Yi disagreed and declared that scientific advancements were more important on benefiting the Solarian society. Eventually, the siblings broke off with each other because of Yi's stubbornness on finding a solution for the council, who promised the society that they would be researching to find a cure for the virus of Tianhuo, causing her older brother to impulsively left Heng alone after he insisted her desire to stay at Penglai. Despite their fallout, Heng had never forgotten about Yi, and only wanted him to live well.

Heng would later send messages to New Kunlun, but was aware that Yi might not be able to read them when she was alive. Eventually, Heng passed away a year or two after the Tianhuo breakout, having succumbed to the virus.

In the end, Heng and Yi are finally reunited in the afterlife, after Yi sacrifices himself to end the Solarians' dying misery.

Heng was described to be naive and eccentric. She was someone who believed that everyone should respect in the natural cycle of life and death. Despite her naïveté, Heng was gentle, understanding and compassionate in nature. This trait of hers was best shown in her relationship with Yi. Although she didn't really understand science, she was still supportive of him and even after their fallout, she never held any anger or grudges against her brother, instead wishing him to live well. She was curious in nature and was always asking Yi questions about things, which he patiently answered and also had a somewhat stubborn, childish and playful side to her, as seen when she pouted at Yi calling the Mystic Nymph "Azure flyer", saying to him that "It's Mystic Nymph! You said you'd let me choose the name!".

Her stubbornness is also what eventually caused a rift in her and Yi's relationship, in some aspects. While Yi believed in science and its benefits for the Solarians, Heng stuck to her ideal of having the Solarians experience life and death the natural way and remained behind in Penglai, even when Yi left her and travelled to New Kunlun.

Yi (羿) is the protagonist and only playable character of Nine Sols. He was a former member of the Ten Sols of the Tiandao Council, who carries the Sol Seal of Innovation.

Yi, a Solarian Scientist called a.k.a Fangshi(方士) is vengeful hero exploring the realm called New Kunlun once home to the Solarians, ancient alien. Yi's quest is to avenge him by Slay Nine Sols, the nine members of the Tiandao Council, the formidable rulers of a forsaken realm known as New Kunlun and the ones who rule over all Solarians.

When this is over, Yi wants to take control of the New Kunlun by taking their Sol Seals, seize all of New Kunlun's authority, expose the ugly reality of Tiandao Council to the Solarians, and return to Penglai, his and all other Solarians' home planet.

Yi has a cat-like appearance, a common feature of Solarians. He has cream-colored fur, a round head, pointed ears and two fur tufts on each side of his face, along with a small, triangular nose. He has big, almond-shaped eyes with large, black pupils and no visible iris highlights. His mouth or eyebrows are invisible, but he mainly expresses his feelings in a way that opens his eyes or frowns. His hands look like human, the fingers of which are tipped with claws instead of nails.

Yi dons an outfit that consists of a black bodysuit, black shoes on white socks, and a Fangshi robe bearing his Sol symbol and Fangshi symbol. The Fangshi Robe's loose cut grants freedom of movement and basic protection during experiments. Yi's choice of a vibrant yellow accentuates his free-spirited, maverick nature.

Yi has a smaller stature compared to other characters, and a jade ring-shaped artificial device on his body that stabilizes the heart. Because Part of Yi's heart fused with the Primordial Roots during a past accident. Later, he uses this artificial ring on his chest to stabilize and resonate with their power. This grants him exceptionally strong regenerative abilities, allowing him to revive at the Root Node even after suffering life-threatening injuries.

Nine Sols (九日) — the rulers of New Kunlun, comprised into a Council made up of some of the most formidable, brilliant, and prestigious members of Solarian society.

The Nine (formerly Ten) Sols are the rulers of New Kunlun and oppressors of the apemen. Each Sol is in charge of their own district and tenets, those of which include: integrity/justice, knowledge, innovation, loyalty, equality, legacy, discipline, benevolence, selflessness, and insight.

Tianhuo (天禍) is a disease which kills any infected Solarians. It is a very deadly virus accidentally created by Eigong when she tried to find the key to immortality.

Tianhuo rapidly destroys all cells within its victims' bodies, and is even genetically passed down through birth. When a Solarian dies infected with Tianhuo, their corpses bloom fungal flowers that breed the Greater Tao Fruits.

Solarians (太陽人) are one of the main alien races from Nine Sols (Game).

Solarians are bipedal aliens that resemble felines. Unlike normal felines, Solarians lack tails.

The average age of death for a Solarian is 140 years.

Solarians behave similarly to humans. They are known for being technologically advanced. While most practice the beliefs of Taoism, by the era of the game many of them have been converted to science.

Clans and classism exist within the Solarians - two known clans include the Jie Kingdom, and the aristocratic Feng Clan from the Shang Kingdom. There are also other kingdoms named Xia Kingdom, Ying Kingdom, and Yumin Kingdom.

According to game developers, Solarians have a matriarchal society.

Solarian language was based on Middle Chinese.