According to her ''
Night Warriors: Darkstalkers' Revenge backstory, Hsien-Ko and her twin sister, Mei-Ling, were born in 1730s China (Qing dynasty). During a time when undead spirits arose and attacked a rural village, their mother was killed in her attempt to save the village, the twins, fought to release her soul from the dark by using a forbidden spell called "Igyo Tenshin no Jutsu". This, in turn, converted them into a jiāngshī ("hopping corpse"), a type of Chinese zombie. Mei-Ling is actually the fú'' ("ward-paper"), a parchment-like talisman that is attached to the front of Hsien-Ko's hat. While the conversion infused Hsien-Ko with magical powers, they are formidable enough that Mei-Ling's presence as the ward-paper is required to keep them in check. The twins' transformation results in them fighting as a Darkhunter as a combined single unit of mind and body. In Hsien-Ko's ''Darkstalkers' Revenge'' ending, the girls free their mother's soul, albeit at the cost of their own lives, but their mother, as a reward, enables them to be reborn as infants in a new life. In Hsien-Ko's
Darkstalkers 3 storyline, which makes no mention of the twins' mother, they discover that they are connected psychically after experiencing the same dream on the night of their sixteenth birthday, but the very next night they both suffer a nightmare and fall into a coma, which in turn sees their collective consciousness transported into Majigen. After awakening in this foreign territory, they find they have gained new powers simply from unleashing the power of an unspecified forbidden spell and team up to fight their way out of the realm. Hsien-Ko has made several other appearances in crossover titles. She appears as a playable character in
Namco × Capcom, and is paired with
Fong Ling from
Resident Evil: Dead Aim as a single unit, while in
Project X Zone she is paired up with
Frank West from
Dead Rising. Hsien-Ko is also playable in
Super Gem Fighter Mini Mix,
SNK vs. Capcom: Card Fighters Clash,
SNK vs. Capcom: Card Fighters 2 Expand Edition,
SNK vs. Capcom: Card Fighters DS,
Marvel vs. Capcom 3: Fate of Two Worlds (where Hsien-Ko and Mei-Ling arrive to ask
Doctor Strange to help them save their mother's soul),
Ultimate Marvel vs. Capcom 3,
Onimusha Soul (redesigned for a
feudal Japan setting), and
Street Fighter: Puzzle Spirits. Hsien-Ko has her own mobile game, ''Lei-Lei's Magical Hammer
, released in the West simply as Magical Hammer
and later remade as Line Drop: Spirit Hunter Lei-Lei
. She was originally planned to be playable in Tatsunoko vs. Capcom, but was dropped due to time constraints. She has also made cameo appearances: in some versions of Marvel Super Heroes where she can be summoned by Anita; in Capcom vs. SNK 2 as a restaurant patron in the Shanghai stage; in Street Fighter Alpha 2'' as one of the party guests, along with her sister, in
Ken's stage; and in
Zombie Cafe in a guest appearance. Her guest appearances in collaboration events within assorted mobile games have included
The Knights of Avalon and
The Samurai Kingdom. Hsien-Ko and Mei-Ling make their first appearance in the second episode of the 1997 anime miniseries ''
Night Warriors: Darkstalkers' Revenge''. The twins travel Earth in an old
T-bucket-style convertible with a trailer resembling a
covered wagon attached. Their personalities, and speech patterns in the English dub of the program, differed considerably; Mei-Ling is the more sensible of the pair and speaks eloquently, whereas Hsien-Ko has a more childlike disposition, and her dialogue often contains modern
colloquialisms or improper grammar (often saying "don't" in place of "doesn't"). She also appears in the 1995
American cartoon series that is loosely based on the games (in the episodes "Ghost Hunter" and "Darkest Before Dawn"), where Hsien-Ko's backstory was altered like those of several characters, in her case her transformation having resulted from her accidentally consuming a substance she mistook for rice that was hidden under a floorboard inside a hut. The character appears in other
Darkstalkers media, such as the comic and manga adaptations of ''Night Warriors: Darkstalkers' Revenge'' by Run Ishida; and Itou Mami's
Maleficarum, as well as in the 2004 card game
Universal Fighting System by Jasco Games.
Gameplay In the games, most of Hsien-Ko's powers "involve floating on air and pulling an impossibly huge collection of deadly items out of their sleeves". According to
Sega Saturn Magazine, unlike the other
Darkstalkers characters, Hsien-Ko "is a mostly defensive character and hence spends most of the game blocking attacks and storing special gauges. She is excellent for countering moves and combos and a number of projectile attacks give her the edge in long range attacks". She is one of the characters that can dash past an opponent and get behind them. Though Mei-Ling has never been a playable character in any of the games, a special move in
Darkstalkers 3 involves her coming out to team up with Hsien-Ko. A
cheat code in
Super Puzzle Fighter II Turbo, where Hsien-Ko and the other characters appear in a
super-deformed state, allows access to Mei-Ling as a playable. According to
GamesRadar, the
Marvel vs. Capcom 3: Fate of Two Worlds version of Hsien-Ko (an
unlockable character capable of interacting with
Chris Redfield) is "an extremely unorthodox character with a number of strange moves and weird mobility". She was judged not good for beginners as her "weird normal attacks and bizarre movement options" and attacks are likely to confuse new players. The
DLC Evil Twin Costume Pack includes Mei-Ling as an alternate skin for Hsien-Ko's model in
Ultimate Marvel vs. Capcom 3. ==Promotion and reception==