King Targor appears in The Roots of Life, the fourth scenario of The World Tree. He's a barbarian, and is stationed in the last enemy Stronghold, behind a quest guard that can only be opened with the Pendant of Total Recall. Defeating him is the goal of the scenario.
King Targor led a brutal tribe of barbarians from Krewlod who turned one of their ancient kings, known only as the Barbarian Tyrant, into a war god, and made sacrifices to him, since they needed a perfect leader to inspire them to greatness. Targor even patterned himself after the Tyrant, hoping to be as strong as the mythical king. One of the barbarian Ancestors accepted this worship as his own to draw power from it, and took on the form of the war god, calling himself Vorr.
Vorr was either driven insane by the violent worship, or was alway insane, and decided to send Targor and his barbarians to destroy the World Tree, the source of all life in the world. When Tarnum, the Immortal Hero, arrived to save the World Tree, his shaman Addar suggested that they should get Targor to stop worshipping Vorr - without the faith of the barbarians strengthening him, Vorr would be far weaker, and Tarnum could defeat him.
Tarnum acquired the Pendant of Total Recall and used it to show Torgar his past, and revealed the reality of the Barbarian Tyrant - how he had poisoned his friends, abandoned their ancient laws and customs, and been cursed to right wrongs for centuries as Tarnum, the Immortal Hero.
"I have spent centuries trying to redeem myself for these crimes. Don't follow my example!"
Targor fell to his knees, shocked by this revelation, and decided to right his mistakes. He went before Vorr to tell him that his people would no longer worship him. He never returned, and Tarnum later found the mutilated bodies of several dozen barbarians, including King Targor. Before going after Vorr, Tarnum buried the dead, and ordered his craftsmen to carve a statue dedicated to Targor's bravery.