Gargantua were a species of large mammalian ape-like animals. At least one lived at .
Gargantua were large, ape-like mammals known for being shy and easily scared, despite their formidable size. They could stand on two, three-toed feet, but walked with the assistance of their three-fingered, more dexterous hands, balled into fists. Gargantua had a deep, loud roar that struck fear in sentient beings unfamiliar with the gentle creatures.
Gargantua had two large, protruding maxillary incisors, which were blunt, as well as four mandibular canines which were still visible with the creature's mouth closed. Their skin was a purplish-gray color, which was exposed on the ventral abdomen, ventral hands and feet, dorsal digits, and face. The distal forelimbs, mandible, and midline dorsal back had auburn fur, whereas the rest of the body had dark brown fur. The forehead down to the nasal dorsum had longer white fur. Gargantua ears were large and superiorly pointed, and the short, flat snout sat near the eyes. The eyes of Gargantua were large, with green sclera and deep black pupils. Their sheer strength was enough to cause massive property damage if spooked.
Gargantua were easily scared, and preferred to run than to fight perceived threats. They were a nocturnal species, and often sought the safety and darkness of caves to sleep during the day.
In the High Republic Era, Jedi younglings Kai Brightstar, Lys Solay, and Nubs were tasked by Jedi Master Zia Zaldor Zanna to assist the Safari droid SF-R3 "Aree" to deliver a ship of creatures from various planetary origins to Sil Gohtta's Nature Preserve. Aree noted that Lys made a special connection with the male Gargantua the ship was transporting, who she affectionately nicknamed "Garganchie." As the younglings and Aree stopped on an Outer Rim planet called Kundu to refuel their starship, Besalisk sisters Slaygh and Braygh were alerted by Garganchie's bellowing roar. Suspicious if it might be a , the sisters boarded the starship, finding Garganchie asleep in his protective compartment. Braygh banged on the transparent barrier, scaring Garganchie out of his sleep, reciprocally scaring the sisters, who inadvertently released the Gargantua from the ship onto their settlement. Afraid of the Gargantua's large size and appearance, the townsfolk screamed and ran, which in turn scared Garganchie, causing him to run into the arid wilderness.
Alerted by the commotion, the younglings used their knowledge of Gargantua to track down Garganchie into a large cave in a ravine, and the creature was happy to see familiar faces. Slaygh and Braygh, mistaking Garganchie's embrace of the younglings as an attack, provoked the Gargantua, sending him back towards the town. Once at the town, Garganchie sought cover on the rooftops, causing mild property damage, eventually climbing atop some larger platforms overlooking the town. The sisters, determined to protect their town, climbed atop the tower, armed with electrostaffs. Meanwhile, the Jedi younglings, distracted by protecting townsfolk from hazards caused by Garganchie's ascent, tried to call to the sisters to not provoke Garganchie further, to no avail. The sisters' provocation caused Garganchie to accidentally knock Braygh and Slaygh off their balance, and they fell off the tower. Garganchie decided to jump after the sisters, catching them in his massive hands, saving their lives. The sisters then realized that Gargantua are indeed gentle giants and were sad to see him leave with the younglings.
Aree and the Jedi younglings finished their journey and released the Gargantua and the other transported creatures into Sil Gohtta’s Nature Preserve, their new home, before returning to Tenoo.