The story of Shakuni

The villain Shakuni, an avatar of Dwapara, the personification of Dvapara Yuga, was the brother of Gandhari in the Mahābhārata. He was very fond of his nephew Duryodhana. He won the kingdom of the Pandavas' for his nephew, as a wager in a rigged game of dice. The dice that were used were made with Shakuni's father's thigh bones and would always do his bidding.

Some sources say Shakuni had been insulted when his beloved sister has been married to the blind Kuru king Dhritarashtra and swore to destroy the Kaurava clan. He achieved this by poisoning the mind of his volatile nephew, and influenced Duryodhana into instigating the war with the Pandavas, which resulted in the destruction of the Kauravas. Thus, he is seen by many as the ultimate cause of the destructive Kurukshetra War

When the Pandavas were given the arid part of Hastinapura, with their great labor and effort, they managed to convert this arid and barren land into a great city called Indraprastha. Soon word of this fabulous city spred and Duryodhana himself came to see the palace. He mistook water for a floor, and fell into it. Draupadi, the wife of the five Pandavas, burst out laughing and insulted Duryodhana by saying that the son of a blindman can only be a blindman. Enraged, Duryodhana returned to Hastinapur. Reading his nephew's state of mind, Shakuni plotted a clever plan to strip Pandavas of Indraprastha. He invited the Pandavas to a friendly game of dice against Duryodhana, being a pastmaster of the game himself. When the game started, he stoked Yudhisthira's gambling urges by letting him win a few minor victories. Soon however, Shakuni used his skills in the game to good effect, and before Yudhishtir could be persuaded to stop playing, he had already lost all his wealth and kingdom. Then Shakuni suggested that he would return all Yudhistir had lost and more if he would put up his brothers at stake. He also taunted Yudhisthira whenever he hesitated from playing. After two more rounds of play, Yudhisthira lost his brothers and their wife, Draupadi, to Duryodhana, thus ensuring his revenge.

Shakuni took Duryodhana's side in the great war at Kurukshetra. He was killed on the battlefield by Sahadeva, one of the Pandava brothers.