Sekigahara

The Battle of Sekigahara (関ケ原の戦い) is largely considered to be one of the most decisive battles in the late Sengoku period.

The battle took place on September 15, 1600 near a town in present-day Gifu Prefecture. Essentially, it is a power struggle for the right to rule the land after Hideyoshi's death. Those loyal to the present yet infant ruler, Hideyori Toyotomi, formed the Western Army and were lead by Mitsunari Ishida. Generals who either hated Mitsunari or desired to see a new land sided with Ieyasu Tokugawa to form the Eastern Army. Historically, Ieyasu barely won the battle largely thanks to Hideaki Kobayakawa's timely defection.

Samurai Warriors
There are many possible outcomes to this battle in Samurai Warriors 2. Every officer who participates in this battle for the Eastern Army starts by seizing the enemy's cannons. They can also protect Naomasa Ii and Masanori Fukushima as they perform overzealous charge against Mitsunari; losing them will lower ally morale. Officers are also asked to guide Magobei Fuse to Mount Matsuo where Kobayakawa remains indecisive in a garrison. If the ploy succeeds, he will defect and the army will gain the winning edge in battle.

Generally, the Western Army officers will be given the chance to route Ieyasu's forces. Minor differences can occur in certain characters' dream stages such as Yukimura, Nene, and Yoshihiro's dream stages. Musashi begins his story here as a warrior on the fallen Western side and has to fight for his survival. There's also the instance where Ieyasu also dies upon his defeat such as in Motochika's story mode.

Kessen
In Kessen, this battle will decide who lives or dies for the remainder of the game's campaigns. The concepts of the Western and Eastern army remain after the battle's conclusion. In the Tokugawa camp, the pre-battle cutscene dramatizes the former Toyotomi general's reasons for joining Ieyasu. Moments before the battle commences, Ieyasu sees a vision of Nobunaga bidding him to continue his legacy. Determined to win, Ieyasu draws out his sword and, whilst declaring his desire to rule, cleaves the mist enshrouding the battlefield. Scoring a victory in this battle acts as the first step for Ieyasu's path as shogun.

By contrast, the Western Army scenario touches on some of the generals' conflicting feelings regarding Mitsunari. Undeterred by news of betrayal amongst their ranks, Mitsunari marches into battle. He swears to protect the Toyotomi family and repay his debt to the late Hideyoshi. If Mitsunari wins this battle, he will pursue the fleeing Ieyasu and be reinforced by the Sanada forces. Losing any major battle after this will result in Mitsunari, Sakon, and Otani's deaths. Winning every battle for the Toyotomi side will secure their family's reign by Mitsunari's hand.

Saihai no Yukue
Sekigahara is the main setting for Saihai no Yukue. The player sees the game from Mitsunari's point of view which villainies Ieyasu. The story explores characters and famous event before the main confrontation.