Sign in to Dominate the World in the Three Kingdoms

Liu Yu traveled to the Three Kingdoms and relied on the system's sign-in summons to unify the three kingdoms and dominate the world... Just when Liu Yu was filled with worries, a mechanical voice suddenly sounded in his mind: "The sign-in system has been successfully bound. The host can sign in every day and get the opportunity to summon historical figures, troops and other special items." Liu Yu was stunned at first, and then he was overjoyed. Isn't this the golden finger commonly seen in novels? He didn't expect that he could also have it. （注意:不要带脑子看……）