O-Mer was a male Cerean Jedi Initiate of the Jedi Order who was captured by Trandoshan hunters, who brought him to the jungle moon Wasskah during the Clone Wars. There, he teamed up with fellow Jedi Kalifa and Jinx, evading their captors in the jungle covering Island Four. Around 21 BBY, Padawan Ahsoka Tano was brought to the moon, and persuaded them to fight openly rather than continue hiding. Following Kalifa"s death, the group—supported by a newly arrived Chewbacca—attacked the Trandoshans' base of operations, overwhelming the defenders when Wookiee reinforcements arrived.