"Liar Game" was a best-seller written by Vivy in an unknown country 25 years prior to the second Liar Game Tournament. This book was found in an antiquarian bookstore by Yokoya Norihiko.
"Liar Game" is not in Japanese, but in a language that Yokoya is fluent in.
"Liar Game" was designed to consist of three volumes, but the third was never released to the public. Therefore, the true meaning behind the novels was never revealed. The novel acted as a potential stimulant for the citizens of the unknown country to start a revolution against the people in power. Therefore, the government banned the publication of the third and final volume, most likely due to the contents being so dangerous that it could finally start a revolution. The third volume did not make it past a censorship inspection, and all copies of the third volume as well as the manuscript were most likely destroyed.
As summarised by Yokoya, the story told by the novel is about a certain country ruled by the worst king in history. If anyone were to bad mouth or oppose this king, they would be captured and brutally killed. This was done under the king's orders, and this king found great pleasure in the killings.
One day, the king arrived at the prison where the captives were held, as he customarily does, and said:
"You are the evil that tries to upset our kingdom. Death sentence is what you deserve. However... there is a chance that there are possessors of great intelligence or education among you, slaying whom may be a waste. So I shall have you all play games. The last man standing shall be forgiven and cleared of all his sins. Moreover, I shall appoint him this country's Chief Statesman. As to the losers... they will be executed on the spot."
And so the games were played by the captives, and the games that were played follow the exact rules and order as the Liar Game Tournament.