Ixlls were descended from omnivorous predators, and had a well-developed feudal society that was generally peaceful; they also had an aptitude for tool and craft making, creating simple but elegant bags and ornaments, as well as black powder grenades they called "exploding stones."
Their language consisted of high-pitched chirps, clicks, and whistles that carried over great distances in the thin air of the pinnacles. They lived in warrens at the tops of the flattened pinnacles, and often collected odds and ends to decorate them. To see in the dark, they had natural sonar. They could fly at speeds of up to 80 kilometers per hour, and glide at around 64 kilometers per hour.
Pinnacle Moon was home to Pinnacle Base, a New Republic fortification used after the fall of Coruscant to Imperial warlords prior to the rebirth of the cloned Emperor. Ixlls often flew through the pinnacles of the moon and darted around New Republic ships. They also demonstrated great friendliness and playfulness with New Republic personnel, and were quickly learning about galactic technology, even learning to use their whistling speech to reprogram astromech droids as pranks. Their legends often centered around tumnors, large predators of their young.
- Dark Empire 2: Devastator of Worlds (First appearance)
- Dark Empire 3: The Battle for Calamari
- Dark Empire 6: The Fate of a Galaxy
- Dark Empire II 1: Operation Shadow Hand
- Dark Empire II 5: The Galaxy Weapon
- The New Jedi Order: Force Heretic II: Refugee (Mentioned only)
- Dark Empire Sourcebook
- A Guide to the Star Wars Universe, Second Edition
- Star Wars Galaxy Series 2 (Card: World Devastators) (Picture only)
- The Art of Star Wars Galaxy: Volume Two (Picture only)
- The Essential Guide to Alien Species
- The Essential Guide to Planets and Moons
- Star Wars Encyclopedia
- The Complete Star Wars Encyclopedia