Shada D’ukal is a member of the Mistryl Shadow Guard, a secretive order of women who hire themselves out as bodyguards and assassins to fund the survival of their devastated homeworld, Emberlene. Timothy Zahn created her for the short story Hammertong: The Tale of the “Tonnika Sisters”, published in the Bantam Spectra anthology Tales from the Mos Eisley Cantina in 1995.
The story is retroactive continuity of a kind the 1990s Expanded Universe specialised in. Two women glimpsed for a second in the cantina in A New Hope were established as Shada and Karoly D’ulin in disguise, on the run from an operation involving a prototype component of the second Death Star’s superlaser. An extra becomes a character; a background shot becomes a heist.
In 0 BBY she was part of a six-person Shadow Guard team led by Manda D’ulin, contracted by the scientists working on the Hammertong project. Her larger arc is Zahn’s later duology, Specter of the Past and Vision of the Future (Bantam Spectra, 1997–1998), where she falls out with the Mistryl leadership — the Eleven — over what avenging Emberlene has actually become, and ends up working with Talon Karrde.
She is Star Wars Legends. The Mistryl are one of that shelf’s better inventions: an entire mercenary tradition built on the premise that a destroyed planet still has a diaspora, and that the diaspora has to eat.