Romance of the Three Kingdoms: The Legend of Cao Cao

Sangokushi Sousouden Online (Hangul: 삼국지 조조전 Online, Mandarin: 三國志曹操傳 Online, Japanese: 三國志曹操伝 Online) is a free-to-play mobile adaptation of Sangokushi Sousouden, the last entry in the Eiketsuden series. It is one of the projects that celebrates Romance of the Three Kingdoms's thirtieth anniversary that was first announced during a similarly themed press conference by Koei Tecmo Japan.

Deuk Gyu is the director. According to his commentary, Sousouden was chosen over other Eiketsuden titles due to its popularity in China and Korea, and because it was considered the most refined title of the series. A PC browser version was written in the contract agreement, but the mobile ports were prioritized first to better target mainstream audiences. He said that PC browser development would begin once the team is satisfied with the results of their mobile version. ThingSoft is responsible for the entire development, but the planning, game design, and artwork are supervised and critiqued by developers at Koei. Any promotional media that has been released in Japanese was due to Koei's insistence.

Artwork was done by artists who have previously worked for TalesWeaver and La Tale. Music for the opening cinematic was done out-house by ASTERIA.

Gameplay
The overall combat system is faithful to the original, but there are efforts to modernize its appeal to new players such as including touchscreen inputs, partly-voiced characters, revamped visuals for characters and strategies, and a lengthy and mandatory tutorial. Battles are sped up significantly than the original, and story events can be skipped automatically. Rearrangements of the original game's soundtrack are spread throughout Online.

Battalions can be formed before battle. Each character has a Cost rating that players have to abide by for the formation of their battalions. The maximum Cost can be raised by gaining more player avatar levels. During the pre-battle screen, the player has the option to increase the performance of their battalion by paying Gold Coins, the in-game currency bought with real world currency.

Each player avatar has expends Energy for battles. It takes five minutes for one energy to regenerate in real-time. They also manage a castle city to produce the resources required for battle. Each facility has one of the player's recruited characters oversee production of consumables like gold, rice, and so on. When the player wishes to extract a resource or update a facility to provide more materials, the building will undergo immediate production. Production has a cooldown timer in real time, though waiting can be bypassed by paying Gold Coins or using tickets.

There are two general modes of play: Epic Mode and Strategy Mode.

Epic Mode faithfully replicates the entire scenario of the original game. It includes the dividing paths that can be unlocked based on dialogue choices that appear before or during battle. Battles that directly affect a story path are the red flaming icons on the world map. Once a battle is cleared, the player can choose to replay it to unlock the other path. Like the original game, specific characters can be unlocked based on the player's choices and progress.

Strategy Mode is the online multiplayer mode with varying secondary options.
 * Siege: PvP castle siege. Each player can choose to either attack or defend one of seventy castles in the game's seventeen provinces. Winners receive large amounts of supplies, gold, and territory to conquer the other players' side. Players are automatically matched according to their level. Allies can either be other players or AI.
 * Incidents: instances and daily events. These battles are often side-stories that focus on a key character. If players completes their chain of battles, they can earn the key character for their collection.
 * Coalition: player guilds for guild vs. guild battles. This mode offers the best rewards for players.

Characters can potentially recruit another character to join the player's forces. It helps to recruit multiple characters to read each character's biography to see their genealogy and continue a chain of recruitments. Characters can be randomly earned by completing battles in either mode. Alternatively, the player may choose to imprison enemy characters during battle and/or coerce enemies to join by occupying their home domain. Whether they will join the player or not varies on the character.

Related Media
The first playable demo of this game was presented at G-Star 2015.