Gorbak is the father of Goro and king of the Shokan people in the Mortal Kombat franchise. He has never appeared in any of the games, appearing only in the non-canon 1994 comic book series and the 2015 Mortal Kombat X prequel comics.
Mortal Kombat comics
Gorbak makes only a minor appearance in the comics following the events of the Mortal Kombat tournament in which Goro and Shang Tsung were defeated by the Shaolin monk Liu Kang. Holding Shang Tsung responsible for the apparent death of his son, Gorbak demands that Shao Kahn allow him to take the sorcerer back to Kuatan to face punishment, offering Kintaro to take Goro's place as commander of Kahn's armies.
Mortal Kombat X prequel comics
After Goro is brutally humiliated and has his arms severed by Kotal Kahn, he returns to Kuatan and falls before his father in shame, begging for death. Gorbak is deeply saddened by what Kotal has done to his son, although he does not grant his son's request. Instead he promises revenge against the Osh-Tekk emperor and rallies an army to march on the emperor's stronghold. Gorbak challenges Kotal to kombat, but ultimately fails and is killed.