Cobak was a xandank from the volcanic world of Mustafar. He belonged to a Jedi Knight that operated on Mustafar at the end of the Clone Wars. When Palpatine ordered the clones of Grey Squad to execute Order 66, the Jedi managed to survive the attack and temporarily escape from the clones. He stored all his personal belongings in a travel chest and hid it among ancient ruins in the Berken's Flow region. Then he ordered Cobak to guard the chest.
Twenty years later a spacer found a datapad that contained the Jedi Knight's last message and followed his instructions to the hidden travel chest. There he discovered that the loyal Cobak was still alive, closely guarding the chest and waiting for the return of his master. The xandank attacked ferociously, so the spacer had to kill it. Written on the beast's collar, he found the code to open the chest.
Cobak was an enemy in the quest "The Jedi's Guard Dog" in Trials of Obi-Wan, the third expansion of Star Wars Galaxies prior to the games closure on December 15, 2011. After activating the Jedi's datapad, the player was led to the location of the travel chest. There, he would have to defeat Cobak in order to open the chest and get the contents.