There were quite a few novels in League of Legends, such as League of Legends: The Emperor Summoner, League of Legends: The Defiant Summoning, League of Legends: The Gale, and so on. According to netizens, Yasuo's master was killed by Rui Wen. It should be in the plot of the novel " League of Legends." The story in the book was about the League of Legends outside of the game's background. It might be different from the plot in the game. So, if you want to know more about League of Legends, you can read the relevant novels. I hope you like my recommendation.😗