An aquatic vehicle was utilized by an attack squad of Mon Calamari from the Mon Cala planetary defense services led by Commander Gial Ackbar during an attack on Imperial Colonel Bergon's aerial landing platform in 18 BBY. Using the vehicle, they were able to go airborne, and then dive underwater when the Empire activated their defenses, allowing the Mon Calamari to get close to the landing platform and launch their missiles, destroying the platform and killing all aboard.
The aquatic vehicles first appeared, albeit unnamed, in Darth Vader (2017) 15, a canon comic authored by Charles Soule, pencilled by Giuseppe Camuncoli, and released in 2018.
The aquatic vehicles first appeared, albeit unnamed, in Darth Vader (2017) 15, a canon comic authored by Charles Soule, pencilled by Giuseppe Camuncoli, and released in 2018.