After Yang Guang Betrayed Me, I Joined Li Yuan and Conquered the Realm

At the end of the Sui dynasty, Emperor Yang launched three nationwide campaigns against Goguryeo to weaken the power of aristocratic clans. The resulting turmoil left the people destitute and gave rise to warlords across the land. Lin Yi transmigrates into this era with a lowly status. Thanks to Empress Xiao recognizing his talent, he rises to the imperial court and devotes himself to the Sui dynasty. But the Sui emperor is arrogant and self-indulgent, refusing to heed unpleasant truths and dreaming of achievements that will overshadow all generations to come. Lin Yi has sound plans, but no power to prevent the Sui dynasty's inevitable collapse. By chance, he meets Xiuning, daughter of Li Yuan of Taiyuan, and the two pledge themselves to each other in secret. Knowing that the future belongs to the Li Tang dynasty, he resolutely joins Li Yuan's camp, rendering extraordinary service in the campaign to capture Chang'an. He takes control of Guanzhong without shedding a drop of blood. But to secure the Tang court, Li Yuan goes so far as to marry his beloved daughter Xiuning to Chai Shao, breaking the promise he once made to Lin Yi. Yang Guang betrayed me, and now Li Yuan's joining in too? Then let's fight! He schemes his way into Wagang, takes command of the military and civil administration, and lays the foundation for the realm. His ambition to turn a spark into a prairie fire spreads throughout the Sui lands. He fights Wang Shichong, defeats Dou Jiande, and becomes the most powerful warlord in the Sui realm. When the Sui emperor hears the news, it is too late for regret. Li Yuan is consumed by rage. Only Li Shimin's eyes blaze with fighting spirit. “The realm belongs to my Li Tang. Anyone who refuses to submit will be slaughtered!” “Heaven's mandate belongs to the Li, not the Lin!”