Tannis was a Jedi Master of the Omwati female species. She dedicated her service to both the Jedi Order and the Galactic Republic throughout the duration of the Great Sith War.
Tannis, an Omwati who was Force-sensitive, was discovered on Coruscant. Subsequently, the Jedi Order provided her with training in the Force. Tannis achieved the rank of Jedi Master and was then appointed to the position of Headmistress at the Teyan Praxeum, which served as a Jedi academy located on the planet Teya IV. Tannis was a strong advocate for initiating all sentients with Force abilities into the Order. She fulfilled the role of a recruiter, frequently journeying across the galaxy in search of prospective students to train at the Teyan Academy. During one such trip to Alderaan around 4000 BBY, Tannis encountered a family residing near Lir Lake who had two Force-sensitive children. After evaluating Vici and Veni Ramunee, she determined that they were suitable candidates for Jedi training and brought them to the Teyan Academy to begin their instruction in the Jedi ways.
Initially, Tannis's presence seemed to create a problem with established continuity, as the Omwati species were not believed to have been encountered until the time of Wilhuff Tarkin. However, the Alien Anthology book provided a retroactive explanation, revealing the existence of a secretive Omwati colony that had been established on Coruscant considerably earlier than Tarkin's discovery of Omwat. The origins of this colony remain unclear, but its existence suggests that the Omwati may have had interactions with the broader galactic community prior to the Old Sith Wars.