Rokkna represented a species of colossal, tentacled sea beings that were native to the planet of Castilon.
A rokkna possessed six tentacles, four eyes, and skin with a green-blue colored pattern. Their pupils were shaped like hourglasses. The size difference between adults and juveniles was considerable; a juvenile rokkna like Bibo could be easily held by a [humanoid], while Bibo's mother was sufficiently large to potentially destroy the entire Colossus platform.
Back in 34 ABY, a young rokkna was discovered within the Karavian Trench on Castilon. Neeku Vozo temporarily took in the rokkna, giving it the name Bibo. When Bibo's mother arrived to reclaim her young one, the Colossus platform underwent an attack until Vozo gave Bibo back. Synara San once spotted a rokkna while she was inside an underwater escape pod.
The rokkna made its debut appearance in "Bibo," a 2019 installment of the television show Star Wars Resistance. Although the species wasn't named in the episode itself, its name was revealed in the Databank on StarWars.com. Jason Pichon produced rokkna concept art specifically for the episode.