- "They're growing healing herbs."
"Nysillin, I believe, one of the most valuable crops in the galaxy."
- ―Ahsoka Tano and Obi-Wan Kenobi
Nysillin, or sillum, was a healing herb grown on Felucia, harvested by Casiss's farming village during the Clone Wars. Hondo Ohnaka's gang of pirates threatened the village into giving away a portion of the herbs, a portion they could not afford to give up, so Casiss hired a group of bounty hunters to fight them. They were soon joined by the Jedi Obi-Wan Kenobi, Anakin Skywalker and Ahsoka Tano, who trained the Felucians to fight for themselves, prompting Ohnaka to give up.
- Star Wars: The Clone Wars – "Bounty Hunters" (First appearance)
- Leia, Princess of Alderaan (Mentioned only) (Misspelled as "nysillim")
- Star Wars: Galactic Atlas
- Star Wars: The Visual Encyclopedia
- Star Wars Encyclopedia of Starfighters and Other Vehicles
- Star Wars: Scum and Villainy: Case Files on the Galaxy's Most Notorious