Koshi Castle

The Battle of Koshi Castle (古志城の戦い, rōmaji: Koshijō no Tatakai) is a stage exclusive to the Warriors Orochi series. It serves as the final stage for all story scenarios in Warriors Orochi. Though Koshi is a district in Japan, the castle is fictional as there are no historical records of it.

Role in Games
The castle is implied to be Orochi's base of operations as the armies fight here for a decisive battle against the snake demon. Koshi Castle is a hidden fortress situated in the bleak wasteland of a semi-active volcano caldera. Surrounded by four cannon bases and garrisons at each corner of the map, the castle is well defended. The gates are surrounded by two drawbridges over a moat of molten lava, which block intruders from entering. When the defenses are ruined, Lu Bu will often serve as the final guardian before reaching the inner keep.

In Shu's story, Zhuge Liang will command the Shu forces at the northwestern corner to repeatedly foil Da Ji's plans in order to bait her into lowering the draw bridges. Da Ji first orders that the front line units charge out, but Zhuge Liang thwarts her assault. Next, she attempts to have Keiji Maeda and Lu Bu attack the Shu forces, but Zhuge Liang attacks and defeats them both before they can fully prepare. Da Ji then attempts to create chaos by summoning phantom soldiers at the northeastern garrison, but the Shu forces find and defeat the sorcerer responsible. She later attempts to stall the Shu with cannons, but the Shu forces take the fortress instead. After the thwarting of all the plans, Da Ji finally lowers the bridges, and is defeated. Soon Orochi arrives with Liu Bei, who asks the allied forces to lower their weapons, but Zhuge Liang exposes the the fraud, and Da Ji appears out of her Liu Bei disguise beaten. Defeating Orochi ends the stage.

In Wei's story mode, Cao Pi will lead the Wei army from the southeastern corner, and he begins by ordering the seizing of all four cannons. Keiji guards the southwestern cannon, Da Ji will guard the northwestern cannon, and will create a rockslide to slow any hostile advance, Masamune guards the northeastern cannon, and will rally the Date forces in the area and the final canon fortress will contain ambush troops that need to be defeated. Once all the cannons have been taken, Cao Pi will order a simultaneous bombardment on Orochi, inducing him to lower the drawbridges. Reaching the first gate, the Wei forces meet Lu Bu, who stands as the final obstacle to Orochi. Defeating Orochi will end the stage.

In Wu's story mode, the Sun family will lead their troops from the southwest. Once the battle begins, Orochi's cannons begin firing at the Wu forces, causing Sun Ce to move to take the cannons. Meanwhile, Orochi's forces begin preparing for an assault on the allied main camp, causing Sun Shang Xiang to move to the southeastern garrison, where she is trapped and caught by Dong Zhuo, forcing Sun Quan to rescue her. Once both the cannons and Dong Zhuo's unit have been stopped, Sun Jian will order the taking of the northwestern garrison, guarded by Da Ji. Once Da Ji is defeated, Lu Bu will open the gates to his garrison, requesting a challenge from the Wu forces. After Lu Bu's defeat, Orochi commends the Wu forces for defeating the general, and lowers the drawbridge to fight them himself. Defeating Orochi ends the stage.

In the Samurai story, Nobunaga's coalition begins at the northeastern corner. Nobunaga first orders the taking of the two southern garrisons, and Kenshin and Shingen separate to take the fortresses. Soon cannons are activated, slowing both generals down, but they are taken by the Coalition. Shingen then begins to insult Lu Bu, forcing Da Ji to restrain the general from moving out on his own. Shingen is later caught in a trap at the eastern garrison, but Zhou Yu arrives with Sun Ce's reinforcements, and attacks the southeastern garrison. Later, Da Ji attempts to move out, but Li Dian, under Cao Pi's orders, appears and attacks the southwestern garrison during her absence. Once Da Ji is defeated, Lu Bu will move out, and, if he is defeated, Orochi will open the gates leading to him. Defeating Orochi ends the stage.

In Warriors Orochi 2, the place is not visited as frequently. In Shu's story mode, Kiyomori uses this location to conduct a ceremony to resurrect his lord. The first mission is to secure the garrison and allowed the other army to arrive. When its done, Da Ji using a storm to block their path. The only way to do is to stop her. Sensing the enemy's cannon fortress is starting to fire, Zhang Liao must take the control of the enemy's. Mitsuhide says that those cannons were useful in their hands, so it is possible to prepare it. The allied cannon's fire attack is successful, only to face Sun Wukong, who produce doubles for himself. But it was instantly defeated. Only Kiyomori remains, the Shu army begin to charge the castle, hoping that they were in time. Even the Shu forces defeat Kiyomori, they were too late to stop Orochi, declares himself for the ultimate battle. The Shu army had no other choice to hurry towards Wuzhang Plains.

The expansion pack also features the castle as Orochi X's Dream Mode stage where he and his cohorts clash against the coalition comprised of the leaders of the four stories of the second game, and Nobunaga.

In Orochi X's story, the stage starts with Kiyomori immediately ordering that the drawbridges to the castle be sealed, and the generals guarding each of the castle's four gates must be rescued in order for the bridges to be lowered. During this time, Zhang Jiao creates phantom soldiers, so Da Ji orders Orochi's forces to target Zhang Jiao instead. Soon, Taigong Wang, Fu Xi and Nu Wa all arrive to help the humans, and they create a poisonous mist around the castle's interior, but Himiko manages to stall them with her own magic. Later, Lu Bu and Tadakatsu Honda will arrive to the battlefield and will challenge Orochi X. Shortly after the defeat of the two, Sakon arrives, and commands the Uesugi and the Takeda cavalry to march on two different fronts. Defeating Cao Cao, Sun Jian, Liu Bei and Sakon will end the stage.

A new Koshi Castle appears in the final chapter of the third game, but this area bears little resemblance to its predecessor. Note that there are two variations of that stage: one in which three devices must be destroyed in order to open the castle's inner gate while another adds two more for the outer gate. Inside, the Hydra will attempt to attack any intruder reaching the throne room. The original version of Koshi Castle is used for three stages only available as downloadable content.

The map on the outskirts serves as the stage for Liu Bei, Cao Cao, Ieyasu and Nobunaga, who face against Susano'o (and Nezha) on one map. The second one also re-used but this time is along with Nu Wa and Fu Xi as their allies.

In Ultimate, the stage reappears when Fu Xi returns to the past, and saves the Heavenly Emperor. After defeating Orochi in the imperial palace, they manage to corner him and his demon army in the castle. Although Nezha is killed in the conflict, Orochi is defeated and sealed.

In Warriors Orochi 4, due to the new dimensional world being created by Zeus and not by Orochi, Koshi Castle is no longer present in any format in the game.