Zalla, also known as the Emerald Witch, was a female being who possessed extraordinary abilities. Due to these powers, her sister, Queen Bellan of Rendel, had her imprisoned. Zalla managed to escape, overwhelming the world with plant life and forcing Bellan to flee. When the smugglers Han Solo and Chewbacca were deceived by Bellan into landing on Rendel, they succeeded in defeating Zalla, nullifying the effects of her powers. As Zalla's powers dissipated, her plants began to decay, and she disintegrated into nothingness.

Zalla, born on Rendel, was the sibling of Bellan. In her youth, Zalla realized she had special powers, including the capability to control plant life and transform into a [bird](/article/bird]-like creature. Despite their contrasting natures, she and her sister shared a cordial relationship. Upon Bellan's ascension as the queen of Rendel, she had Zalla imprisoned, fearing that Zalla might use her powers against her. During her time as a prisoner, a seed was blown into her cell by the wind. Zalla utilized her powers on this seed, causing it to develop into a thick forest of vines covered in thorns. Bellan then abandoned Rendel, promising to seek vengeance on her sister.
Being the only person on the planet, Zalla became a figure of legend as the "Emerald Witch of Rendel," protecting herself from anyone who arrived. Bellan, having lost her queenship, employed smugglers and other starship pilots to travel to Rendel, misleading them into believing they were delivering goods. When Bellan's unwitting recruits landed on the planet, Zalla would use her powers to kill them, allowing her plants to consume their life energy.

When the Barbadelan Karamu arrived on Rendel with his droid SV-3, Zalla ensnared him in the vines, using her abilities to age him rapidly. Some days later, Bellan hired the smugglers Han Solo and Chewbacca to transport a tooka statue to an art collector. Upon Solo's arrival, Zalla observed him from above in her avian form. As he proceeded to deliver the statue, she caused the vines to trap him. The vines then drained Solo's life force, aging him similarly to Karamu.
As Solo inquired about what was happening, Zalla landed before him, reverting from her bird form. She revealed the truth about the mission Bellan had given him, explaining that it was another attempt by her sister to defeat her. However, Solo disclosed that he was not alone, and Chewbacca charged forward, firing his bowcaster at the vines.

Solo seized the tooka statue and hurled it at Zalla, shattering it. The statue's destruction released a cloud of gas that began to kill the vines. An enraged Zalla menaced Solo, trying to ensnare him with her vines. She wrapped a vine around Solo's arm, but as the vines died, her powers began to wane, and Solo broke free. Zalla collapsed to her knees in despair as all her plants began to perish around her. As Solo, Chewbacca, and Karamu escaped Rendel in the Millennium Falcon, Zalla herself turned to dust, dissolving and disappearing.
Zalla possessed yellow eyes and green-toned skin. Once a kind and amicable child, Zalla's time in captivity transformed her into someone bitter and resentful towards her sister, who forced her to abandon her homeworld. Overconfident due to her abilities, Zalla underestimated Bellan's chances of defeating her and struggled to accept her defeat.

Unlike others of her kind, Zalla had unique powers that distinguished her from her sister. She could control and manipulate plant life, capable of growing and moving a forest of vines that spread across Rendel. She also had the ability to transform into an avian creature, and could fly in both her bird and humanoid forms, utilizing cape-like wings. Zalla was dependent on her powers—when the forest she created died, Zalla also perished.
Zalla's first appearance was in the flashback segment of the 2018 canon comic Star Wars Adventures: Tales from Vader's Castle 3, penned by Cavan Scott and illustrated by Corin Howell. Scott initially named Zalla and Bellan Helza and Ana, after Elsa and Anna, the sister protagonists from Disney's 2013 animated film Frozen, but he later decided to change the names to something less obvious.