PLNK - series power droid / Legends PLNK - series power droids , nicknamed " plunk droids " for their distinctive vocalizations , were four - legged power droids manufactured by Industrial Automaton during the Clone Wars . They spoke a form of droidspeak similar to Gonkian and functioned as containment and refueling units for liquid tibanna gas , which they equipped various starships and equipment with . Though not built with the near - limitless capacity of standard power droids , their tibanna - driven generators were enough to provide the Grand Army of the Republic ' s listening posts with sufficient power to execute their needs . The droids served the Republic Navy , working aboard " Venator " - class Star Destroyers ; as well as the Confederacy of Independent Systems , counting freighters that passed through the Separatist blockade of the Gwori system . PLNK - series units were also used on Republic - affiliated worlds such as Coruscant , Rodia , and Mandalore . Characteristics . The PLNK - series power droid was designed for storing and refueling liquid tibanna gas . They were additionally built for refueling starships and equipment and performed simple tasks in spaceports and military bases . To increase their capacity for tibanna , the droids were based on a " stretched " designed of the GNK power droid and had four legs , as opposed to the two of the GNK series . Lacking both weapons and a programmed gender , the PLNK - series were equipped with feet that allowed them to waddle along . They had a slow moving pace , weighed down by a heavy internal tibanna tank and tibanna - powered generator . A single unit carried an internal pump for loading and discharging liquid tibanna through its externally mounted hose and nozzle ; the fuel hose ran from the droid ' s left side to the nozzles holstered on its back . Their actions could be controlled by a main panel for system diagnostics located on their front side . The droids spoke a form of droidspeak similar to Gonkian , saying " plunk " as they shuffled about and hence earning them the nickname " plunk droids . " They also understood Galactic Basic Standard but were unable to speak it . Although unequipped with the near - limitless power generation of a standard power droid , each PLNK - series model possessed a tibanna - driven generator that was capable of supplying enough power to satisfy the needs of Republic listening posts until its tibanna supply ran out . Three plunk droids were enough to power a single listening post and could alternatively be used as detonators to destroy an outpost in case of enemy insurgency . In the service of the Confederacy of Independent Systems , plunk droids were thought to have some defective circuits that led to miscalculation . Like other power droids , plunk droids were encased in heavy shielding , mainly over their fuel reservoirs , and colored duranium plating — ranging from dark green to gray , brown , and gold — to safeguard their highly flammable tibanna contents . To further protect their cargo , the units featured heightened security and safety protocols , but were still restricted by highly limited programming and artificial intelligence . The droids ' self - preservation programming sometimes gave them cause to run away from their owners when " spooked " or agitated . History . PLNK - series power droids had begun to be manufactured by Industrial Automaton by the time of the Clone Wars . They were in the service of the Separatists , counting freighters passing through the blockade of the Gwori system to the Gwori Revolutionary Industries shipyards . When B1 battle droids noticed one too many freighters in a convoy , they dismissed it as a calculation error made by the plunk droids , whom they claimed possessed defective circuits . Plunk droids were also used by the Republic Navy to refuel BTL - B Y - wing starfighter s , bombers introduced during the war that , unlike most starfighters , relied on liquid tibanna instead of fusion generators as a power source . The droids served aboard the " Venator " - class Star Destroyer " Resolute " in the Open Circle Fleet of the Republic Navy and could be seen shuffling about the hangar bay of the vessel , where Y - wing bombers , LAAT / i gunships , Delta - 7B interceptors , and V - 19 Torrent starfighters were housed . A trio of plunk droids , containing liquid tibanna , served as the power source for the Grand Army of the Republic listening post Rishi Station on the Rishi moon , which was used to monitor a portion of the Outer Rim Territories for possible invasion by the Confederacy of Independent Systems . When Separatist BX - series droid commandos captured the station , the clone troopers manning the facility decided that it was necessary to destroy the installation to warn Kamino , the site of the Grand Army ' s cloning facilities , of the impending Separatist attack . The troopers rounded up the three plunk droid units and wired them together in order to detonate them using a thermal charge . When the remote detonator failed to sync up with the charge , clone trooper Hevy sacrificed himself to manually trigger the device , destroying the three plunk droids along with the installation . Plunk droids were used on the planet Rodia , where one such droid stepped in to fuel Jedi Master Obi - Wan Kenobi ' s Delta - 7B interceptor after he landed in Kay - Tap square to intercept the bounty hunter Cad Bane . The droids were additionally employed by the Republic on Coruscant and were involved in preparations for the departure of the Royal Naboo J - type star skiff , which was to take Senators Padmé Amidala and Rush Clovis to a diplomatic meeting with Senator Lott Dod on Cato Neimoidia . Shortly afterward , plunk droids were dispatched with a Republic fleet sent to invade the planet Geonosis and halt the production of Separatist battle droids in Archduke Poggle the Lesser ' s droid foundries there . The power droids were present aboard the Star Destroyers of the fleet when the initial body of troops was deployed . Sundari , the capital city of Mandalore , made use of plunk droids in one of its spaceports , where the units were sometimes observed by Mandalorian civilians during their operations . Behind the scenes . Plunk droids were created for the 2008 television series " " and first appeared in the background of the episode " Shadow of " Malevolence " , " which aired on October 10 . The droids were first named in the StarWars . com episode guide for " Shadow of " Malevolence " . " They later had a more active role in the October 24 episode , " Rookies , " and could be seen once again ambling around a hangar bay in " Jedi Crash " as well as " Storm Over Ryloth . " They were also used in the series ' , appearing extensively in the background of scenes in multiple episodes . They were given the " PLNK - series power droid " designation in the 2009 " Scavenger ' s Guide to Droids " , published by Wizards of the Coast , which also greatly expanded the droids ' features . The appearance of plunk droids is very similar to that of the GNK and EG - 6 droids of the original " Star Wars " trilogy . In an interview published in " Star Wars Insider 115 " , " The Clone Wars " Supervising Director Dave Filoni states that the name " plunk droid , " as well as the sound that the droids make , is a play on the name of designer Kilian Plunkett . Plunk droids also appeared in the 2011 non - canon ical video game " " that adapted " Rookies . "