Cobak was a xandank creature hailing from the lava-ridden world of Mustafar. He was the loyal companion of a Jedi Knight who was stationed on Mustafar as the Clone Wars neared their end. When Palpatine gave Grey Squad's clone troopers the command to carry out Order 66, the Jedi, against all odds, survived the initial assault and managed a brief escape. Before going into hiding, he placed his prized possessions within a traveling chest and concealed it within the ancient ruins of the Berken's Flow area. Following this, he instructed Cobak to protect the chest at all costs.
Two decades later, a spacer stumbled upon a datapad containing the final communication from the Jedi Knight. He followed the instructions to the hidden travel chest. Upon arrival, he found Cobak still alive, faithfully guarding the chest and awaiting his master's return. The xandank launched a savage attack, forcing the spacer to kill the beast in self-defense. The code needed to unlock the chest was inscribed on the creature's collar.
Cobak appeared as an antagonist in "The Jedi's Guard Dog" quest within Trials of Obi-Wan, the third expansion pack for Star Wars Galaxies before the game servers were shut down on December 15, 2011. Upon activating the Jedi's datapad, players were directed to the travel chest's location. There, they were required to overcome Cobak in battle to gain access to the chest and its contents.