''Kessen'' is a video game developed by Koei and one of the first games released for the UsefulNotes/PlayStation2. Taking place in FeudalJapan, players live out the last days of the Sengoku Era with the rivarly between The Toyotomi and Tokugawa clans to see who would rule over Japan beginning at Sekigahara and climaxing (possibly) at Osaka Castle. Unlike the sequels ''VideoGame/KessenII'' and ''VideoGame/KessenIII'' gameplay is very different from them. Each character has a number of troops at his disposal and can issue special attacks.

The game starts out as Ieyasu Tokugawa in control of the Eastern Army, after beating it the first time the players can then play the other side in control of Mitsunari Ishida and The Western Army. Alternate routes and battles can take place depending on victories and defeats.
!!Kessen provides examples of:
* AlternativeCharacterInterpretation: InUniverse example. Everyone gets these depending on which side you play as. In The East Ishida is reviled as a tyrant and Tokugawa a man who seeks to bring Nobunaga Oda's dreams of a united Japan to reality. In The West Ishida is a Hero who has sworn to protect The Toyotomi whilst Ieyasu is seen as a man who seeks to steal the land and hard earned peace.
* CueTheSun: The ending for both sides show the sun raising up and each side standing on a cliff overlooking it symbolizing the new era that has been brought.
* DirtyCoward: Kobayakawa. Kikkawa is one as well
* TheDragon: Sakon for Ishida, Tadakatsu for Tokugawa
* DragonInChief: The Eastern Army leaders for Toyotomi Hideyori.
* DrowningMySorrows: Fukushima does this on The Eastern Side realizing he may have doomed The Toyotomi by helping Ieyasu win.
* EvilOldFolks: Josui Kuroda, heck his music should tell you that he's up to no good. http://www.youtube.com/watch?v=LWqI3Mo3aP8
* FaceHeelTurn: Officers can pull this if you perform poorly as they can defect.
* HeelFaceTurn: And they can also do this as well if the battle goes right. Notables are Kobayakawa, Masanori Fukushima, Josui Kuroda, Takatora Todo, and Masamune Date.
* HelmetsAreHardlyHeroic: Averted, everyone in this game wears one like they did in real life. Though doubtful they had the designs they do in the game.
* HereWeGoAgain: If certain routes are taken (such as The Toyotomis winning at Osaka Castle and driving Ieyasu out of the capital) [[spoiler:The final battle of the game will take place at Sekigahara where it began]]
* HeroicSacrifice: The Retreat from Hakone for The Eastern Army: while the main army retreats, warriors and volunteers stay behind to hold off the pursuring Western Army to the last man. [[spoiler:Ieyasu is one of them refusing to abandon his men]]
* HiddenBadass: Shimazu is older and has less troops but doesn't mean he can't hold his own against larger armies.
* LastStand: Osaka Castle for The Toyotomis and Edo for Tokugawa.
* ManlyTears: Naomasa and Yasumasa shed them when Ieyasu stays behind as well during the retreat at Hakone as part of the rearguard.
* MyNameIsInigoMontoya: Sakon pulls this off at Kusegawa when he attacks Ieyasu
* NiceHat: Everyone in this game wears a cool looking helmet. Except for Anko, he's just bald.
* RealLifeWritesThePlot: Guys who are in your army in the first couple of battles won't be in later stages. Makes sense since Tadakatsu and Naomasa had died by that time and their sons had replaced them.
* TheLoad: Kobayakawa and a number of officers for The Western Side. Heck no matter how many times you win, Kikkawa will never follow your orders. Hidetada Tokugawa for the East is one as well. Despite having large number of troops (almost as much as his father has) he can be defeated by much smaller armies and not a whole lot of use in battle.
* WeAreStrugglingTogether: While The Eastern army is loyal to Tokugawa, The Western army in contrast struggles to work together and follow Mitsunari's orders at the beginning with some of them planning on not doing anything or betraying him.
* WhatIf: This happens through the Western Side, with Mitsunari winning at Sekigahara and him (or Yukimura) going on to establish a reign ruled by The Toyotomis
* YouAreInCommandNow: If defeated on their side, Mitsunari and Josui Kuroda pass on command of The Western Army to Yukimura Sanada before they [[spoiler:die]]
* YouKilledMyFather: Yukimura vows revenge against Tokugawa when he discovers his father Masayuki Sanada has been slain by assassins. Similarly Naotaka, the son of Naomasa Li swears to avenge his father's death as well in one of the possible routes.