Sign-In at the Imperial Palace: Diao Chan Exposes My Eunuch Disguise

[The protagonist rises to power across the realm from the imperial palace] [Plot-focused] His soul transmigrates into Huang Xu, son of Huang Zhong, one of the Five Tiger Generals. Huang Zhong is in his thirties and at the peak of his strength! Yet Empress He has him abducted into the palace because of Huang Zhong. Fortunately, he activates the Emperor's Sign-In System. Sign in at the imperial palace to obtain potatoes, sweet potatoes, corn, the curved-plow, refined salt, medical knowledge, military strategy, swordsmanship, the art of steelmaking, general cards... Sign in at the imperial garden to obtain the God of Slaughter Bai Qi's God-Slaying Halberd. Sign in at the imperial study to obtain one epic-grade general summon card for Yue Fei. Sign in at the Imperial Medical Academy to obtain superlative medical skills and the ability to bring the dying back to life. Throughout the Han imperial palace, there are places to sign in, and rewards to be had everywhere. But one day, while Huang Xu is signing in at the palace, he never expects Diao Chan to discover his fake identity.