Gnulliths were a branch of biotechnological breathing apparatus worn by the Yuuzhan Vong. Like all Yuuzhan Vong equipment and devices, these were living organisms: in effect, they functioned as an atmospheric filter.
The gnullith was a form of biological breathing mask used by the Yuuzhan Vong that allowed the wearer to breathe in any non-corrosive or fluidic environment containing oxygen. Resembling fleshy, starfish-like creatures, the gnullith sealed itself over the mouth of the wearer and inserted a long proboscis down the throat in order to provide the host with a supply of breathable air. While uncomfortable to use, unlike most Yuuzhan Vong biots, gnulliths did not inflict pain on the wearer. Unlike breath masks, gnulliths could be used indefinitely as they did not use air canisters or require replacement filters.
The Yuuzhan Vong created a hybrid gnullith-villip hybrid combining the function of both a communication device and breathing apparatus. In conjunction with lungworms and vacuum cloakers, the gnullith-villip hybrid allowed a Yuuzhan Vong to breathe and communicate in vacuum environments.
- The New Jedi Order: Vector Prime (First appearance)
- Invasion: Rescues 3
- The New Jedi Order: Balance Point
- The New Jedi Order: Edge of Victory I: Conquest
- The New Jedi Order: Edge of Victory II: Rebirth
- The New Jedi Order: Star by Star
- The New Jedi Order: Destiny's Way
- The New Jedi Order: Force Heretic I: Remnant
- The New Jedi Order: Force Heretic III: Reunion
- The New Jedi Order: The Unifying Force
- The Complete Star Wars Encyclopedia
- The Essential Guide to Alien Species
- The New Jedi Order Sourcebook