The strategy board game "Romance of the Three Kingdoms IV" (SANGUO 4), released by KOEI in 1994, is a milestone work in the Japanese Koei"s "Romance of the Three Kingdoms" series, available on platforms such as DOS, WINDOWS, PC98, PS, and SS. "Romance of the Three Kingdoms IV" completely abandoned the previous keyboard-based control system in favour of mouse operation. The graphics have also made significant progress compared to earlier titles in the series. However, the biggest change in the game is undoubtedly the character settings. In addition to the usual abilities (i.e., numerical attributes), 24 special abilities have been added. The relationships between characters and rulers now include bloodline factors and hidden compatibility between monarchs and ministers, giving the game a strong humanistic colour. In terms of military actions, it mainly inherits the model of the previous three games, divided into two parts: field battles and city battles. When the city gates are breached and the defending side has no retreat, they can choose to engage in a duel with troops or martial prowess. The combination and variation of strategies play an important role in this edition. Overall, it is a highly successful strategy game, regarded by fans of the series as the most classic installment in the "Romance of the Three Kingdoms" series.