Romance of the Three Kingdoms IV: Wall of Fire (JP: Sangokushi IV) is the fourth entry in Koei's long-running strategy game franchise based on the historical novel Romance of the Three Kingdoms. The subtitle "Wall of Fire" is a reference to the Battle of Chibi (Battle of Red Cliff) in which a navy commanded by Cao Cao of Wei was destroyed in a successful fire attack. The loss stunted his conquest's momentum and was partially responsible for allowing two other kingdoms, Wu and Shu, to rise to power.
As in other entries of the series, Wall of Fire is a turn-based strategy game in which the player takes control of a ruling officer with the ultimate goal of conquering all of China through warfare and diplomacy. Each in-game turn spans a single month, during which time officers under the player's control can be assigned various domestic, diplomatic and militaristic tasks. These tasks rage from overseeing farmland and attempting to court officers to the player's side to drafting and training new soldiers.
When going to battle, the player must first organize the troops under the participating officers by assigning specific numbers of soldiers to each officer, as well as assigning a unit type. In battle, each turn lasts a single day, during which each unit under the player's control is granted one movement action and one attack or special action such as taunting the enemy or proposing a duel.