Ōsaka Castle

The Siege of Osaka (大坂の陣, Ōsaka no Jin) is the Toyotomi's last stand against Ieyasu. The Toyotomi forces are vastly outnumbered and it is Yukimura's final battle. Historically, this battle took place near the end of a campaign between the factions. The games particularly focuses on the decisive summer battle.

Samurai Warriors
In Yukimura and Kunoichi's version of the battle in Samurai Warriors, the Toyotomi army lures the Tokugawa advance force within range of Sanada-Maru (called Sanada ward in the sequel), a small battery of cannons on the outer walls of Osaka Castle, and destroy them. To counter, Ieyasu sends a cannon unit to destroy Osaka Castle's main gate. After stopping both advances, the two warriors head to the main camp to request for reinforcements from Hideyori. Whilst doing so, they also have the choice to stop Masamune from entering the castle's western gate. Though their lord promises to reinforce, he is stopped by his overprotective retainers who distrust Yukimura. Seeing the battle lost, Yukimura makes a final charge for Ieyasu's camp. After fighting his way past a Tokugawa trap, he arrives to his destination. His arrival causes Ieyasu to flee from the field and pits him against Hanzo. Following Hanzo's death, the players either sees Yukimura's endings or Kunoichi's movie ending.

During Hanzo's story mode, the player is given a chance to foil Yukimura's tactics as well as his charge through ally ranks. The ninja is also given the task to assassinate any remaining Toyotomi followers. Once he kills Hideyori and Yukimura, the player sees his movie ending. Alternatively, Hanzo also infiltrates the castle in his second ending to uncover any information regarding a conspiracy to end the Tokugawa family. Whilst in the castle halls, he encounters Goemon and Kunoichi.

This stage also serves as Ina's lower path ending in Samurai Warriors: Xtreme Legends. For this scenario, the army faces Hideyoshi to decide the land's new ruler. Driven by her lust for battle, she mercilessly slays her opponents. In the castle's burning wreckage, she realizes the true price of war and her new life as a warrior.

In Samurai Warriors 2, the main scheme of events remain similar to Yukimura's first story. New defenders for the castle include Musashi, Magoichi, and others. The castle's guardians either protect or reclaim the Sanada ward from the enemy while defending the castle's gates from the Tokugawa cannon. They can also defeat bandits that attempt to raid the castle's storehouse. If they successfully deflect the Tokugawa advances, Hideyori will be inspired to fight for his army and leads an all out offensive. During Yukimura's story mode, they will also gain a new ally when Kanetsugu defects.

For the Tokugawa army, they get the Uesugi troops led by Kanetsugu if the player is on the Toyotomi side. The primary objective is to stop the Sanada ward from firing. Attackers also need to open the other castle gates once they're inside. To lower enemy morale, they may also take the enemy storehouse. Once they proceed into castle's top level, they battle Yukimura and Hideyori. However, they are actually doubles biding time for the real Hideyori's escape. Determined to win, Yukimura commences his death charge while his lord tries to flee from the field. Defeating them at this point ends the stage. Ieyasu complements their final resistance, proud to see them fight until their end, and comparing Yukimura to Shingen.

In Samurai Warriors 3, some changes are made. Sanada-maru is a fortification of arquebusiers, not cannons. From there it is heavily surrounded by Tokugawa forces and is defended by Yukimura. Three Tokugawa cannons that face the castle walls can be manned to give their engineer extra time to put a hole in the wall.. The Toyotomi gain Kai and Kunoichi. In Kiyomasa and Kanbei's stories, Kiyomasa, Sakon, Muneshige, and Masanori also appear as defenders.

The Tokugawa regains Hanzō for their side in every mode but the Sengoku History mode. Kanbei, Kanetsugu, and Magoichi are added in various character scenarios.

Warriors Orochi
Orochi had Sun Jian imprisoned in this castle in the first game. Sun Ce meets up with Sakon and the strategist reveals the captured leader's location. Players are directed to control or lead Sun Ce and his army through the castle and rescue Sun Jian. The father and son's reunion triggers an escort mission to an escape point southeast of the castle. Along the way, they may be able to save the other prisoners and have them join the breakout. The battle ends in victory should the player successfully reach the escape point with Sun Jian in tow.

Warriors Orochi 3 has the coalition protect the Yashio'ori from the demon army's invasion. Players may opt to defeat the advancing forces or go inside the castle grounds to catch Sun Wukong. Should they go with the latter, Sun Wukong's attempts to close the castle gates will be rendered useless. Nezha's participation in this battle will also trigger Lu Bu's appearance as a third party unit. He can be converted into an ally officer by approaching him with Diaochan.

Kessen
Kessen sets Osaka Castle as one of the possible conclusions for the West or East. Either the Western side can lose a string of battles or the East can have a straight winning streak to unlock it.

The map positions the Tokugawa forces in either the southwestern corner, the southern regions and/or the center. Toyotomi defenders have limited options to counter them from the north or northwestern quadrants. By default, the Tokugawa have more units and can create larger armies than the Toyotomi generals. The Toyotomi have fewer numbers but are equipped with more cannoneers and are have advanced mobility compared to the sluggish Tokugawa units.

Players who play from the Eastern perspective will often fail to convince any adversary to bide time or defect. They do have the option of charging or waiting for their foes to come towards them due to their massive army. The defensive approach may require the player to strategically position a giant unit to take the brunt of Toyotomi cannons' damage. Offensive Eastern units may become a victim to ambushes if they charge in too recklessly. Regardless of whatever strategy is employed, the Tokugawa should have a few idle artillery units prepared to counter the West's damaging spear and cavalry units. On most difficulty settings, Yukimura is prone to targeting Ieyasu if he remains idle within the default positioning. The player can equip an army of kunoichi to counter Yukimura's own legion of ninja, but they might struggle if he is escorted with one of the Toyotomi canonneer units. Cautious players might want to try repositioning Ieyasu if they wish to protect their main general from their onslaught.

Western defenders will find themselves struggling if they attack the Tokugawa forces head-on; they may fare well in initial skirmishes, but they will suffer once the Tokugawa cannons come into range. It may prove beneficial to the player to split their forces and target Ieyasu's main camp directly in the west, using the forces in the center to distract the Tokugawa besiegers. The worst possible start for this map with this strategy is facing an unmoving East, as they will often try to cut off the generals only when the player commands their troops. Alternatively, the player can choose to rely on their army's maneuverability to constantly avoid long-ranged conflict and close in with their deadly melee fighters. Depending on the difficulty setting, players can ask Fukushima and/or Todo to defect to their side as long as they avoid attacking them prematurely and do not lose too many units. If they are able to hold out with high morale very late in the battle, Hideyori will arrive as reinforcements.

If the Toyotomi side emerges victorious from this battle, the story's final outcome will be decided in a fictional battle at Sekigahara.