Kessen

Kessen, which literally means "decisive battle" in Japanese, is a real-time strategy game for the PlayStation 2 produced by Koei and published by Electronic Arts. Like Dynasty Warriors 2, it was one of the first titles of its genre to be featured for the console. The game is set near the end of the Warring States period in Japan, beginning with Sekigahara and historically ending with the Osaka Campaign.

Before the player begins a story, they're entreated to a message by the producer, stating that the game fulfills his desire to create a movie that could be controlled. To follow suite with this statement, the players can choose to win or lose battles to experience a different storyline. Events that occur can either be abridged dramatizations of history or completely original yet fathomable scenarios. Cinematics and the music are similar to the samurai film genre with characters adopting a tone complementary to the setting.

Players begin the game as Ieyasu Tokugawa and are free to eventually unite the land or lose their conquest. After the last confrontation, they can play a second time with Mitsunari Ishida. Once both scenarios are cleared, players can choose their next leader and adjust the difficulty level to their liking. Each time the player completes a scenario, the branching storylines they earn can be seen in the "Battle History" option at the starting screen.

It is followed by two other titles, Kessen II and Kessen III. Though each title shares the same name and similar gameplay elements, neither of these are direct sequels. Kou Shibusawa serves as the producer for all three titles. The main composer for the series was Reijiro Rokuro, who is known for his orchestral work in Japanese TV dramas and select NHK taiga dramas.

Gameplay
Each storyline is a continuous string of battles between the two armies. Story segments take place before the planning and strategy phases. Special cutscenes can also occur during battle.

Planning
After the narrated introduction, players are entreated to begin preparations for the incoming battle. The commander privately meets with his two loyal generals to check their situation. The vassal on his right presents information on which officers are sided with the enemy. Usually, information includes their allegiance, their skill chart, and the number of men they possess. On level 4 and 5 difficulty, however, the player will only be able to see their names. Based on this information, the player needs to decide which enemy candidates should be asked to defect or bide time.

The vassal on the left presents information for the player's army. Here, they can decide who to send into battle. A portion of the generals are mandatory and cannot be switched out so only candidates may be changed. Armies can also customize their unit types based on the players' available resources. Unit types are as follows:
 * Footmen - average soldier with a sword. Commonly used defensive type.
 * Spearmen - strongest footmen unit available to every general. Can create a spear wall to repel the enemy's advance. Works well against other foot armies but has mixed results with mounted types.
 * Bowmen - archers on foot. While they are good for ranged conflicts, they are weak with head on conflicts. A good support unit.
 * Riflemen - troop with long ranged rifles. They can perform a normal volley that damages footmen or a "Triple Volley" skill to greatly wound any type. Can either be men or women.
 * Horsemen - swordsmen on horses with a decent defense. Good against footmen but weak against other mounted units.
 * Lancers - horsemen armed with spears. An army of lancers can use "Charge", which allows the entire army to rush through an enemy and appear on their flank. Overall powerful unit.
 * Cavalry - riflemen on horseback capable of sniping with the "Flying Fusillade" skill. Best used at a distance to shoot the units who aren't on horses. Weak against other horsemen types. Can either be men or women.
 * Kunoichi - troop type that dominates the others and is the fastest unmounted type. A very destructive troop to let loose on the enemy with the "Kunoichi" command. However, they come in low numbers and are weak to ranged or surprise attacks. Often reserved for the highest ranking officers.

Army formations can also decide what skills an officer can use and may increase their offensive or defensive capabilities. Each general is already set with their preferred formation but this can be adjusted to the player's liking. After the player passes this segment, their decisions remain final and cannot be changed past this point.

Strategy
Literally the final war council before marching into battle. After the generals report the positions of the opposing side, the player is allowed to adjust their army's position on the field. They can individually move units to green or pink spots designated on the map and can change the direction they're facing. Generals can be ordered to remain idle, target an enemy unit, or move to reinforce an ally. If they're positioned on a pink circle, they can lie in wait for an ambush or build a fortification around them to prevent being surrounded by many enemies. Alternatively, the player can choose to use the preset strategies the game gives, which are Offensive, Defensive, Army Stand Firm, and Army Attack.

Battle
At the start of each battle, the player's right hand man reports the conditions for victory as well as any reinforcements planned for the enemy or player. He asks to confirm their orders for a final time. Here, the player can choose to go as planned or abort it by charging the enemy or standing firm. Once they decide, the battle finally begins.
 * Generals can be selected by the cursor on the map, switching through the trigger buttons, or through a roll call menu. They can be ordered to march, reinforce an ally, or attack. Though the player can set targets for them, the general's path of movement is set by the computer.
 * Officers are given a set of number of special maneuvers to use based on their unit type. They are often more damaging than normally attacking and require a given amount of the officer's zeal to perform them. Zeal can usually be restored by rallying with the commander or when an ally destroys an enemy unit. Particular generals may also request to attack one of their rivals. If the player allows them to indulge themselves, they'll gain a substantial zeal boost.
 * Army morale affects the unit's fighting power. If morale is low, the unit does less damage and loses troops at a quicker rate. 100 is the best condition while 20 or below will cause the army to flee.
 * Troops can suffer from fatigue if they're used too much in battle. To restore a unit to their optimum state, stop their movements and given them to time to rest.
 * Duels between generals take place randomly and are never denied. While the results only affect army morale, they inevitably lessen the loser's performance. Leaders are not exempt from this event.
 * A feature exclusive to this title is the general's willingness to accept an order. Loyal units will accept any change, no matter how minor or eccentric it maybe. Protesting units obey but experience a drop in zeal in the process. Reluctant officers may also refuse a command and continue their current position. Doing so decreases their morale and zeal. Accurately gauging an officer's loyalty during the planning stage helps prevent the latter two from happening.
 * Victories are often decided by numbers. If an army has less than 50 men, they will lose their ground on the field and forced to flee. Decimating an enemy can be done through normal conflict or by attacking with powerful officer skills. A retreating unit that has a low amount of men can also be pursued and may have a good portion of their men cut down. However, if the fleeing unit successfully escapes with a high enough morale, they can gather more men whilst reforming their army.

Characters
For the English version of the game, generals are given shorter names for easier recognition. These abbreviations can either be one of the figure's names or an amalgam of both their names to distinguish themselves from others. Some examples include:
 * Tada Honda = Tadatomo Honda; Honda = Tadakatsu Honda
 * Yuki Sanada = Yukimura Sanada; Yuki = Hideyasu Yuki
 * Maeda = Keiji Maeda; Toshi = Toshitsune Maeda

Usually, these names are kept exclusively for the planning and battle stages though they can also be mentioned during cutscenes. Leaders will sometimes have their given name spoken instead. In the pause menu during battles, players can see each figures' full name and a brief biography of their exploits.

East

 * Ieyasu Tokugawa
 * Tadakatsu Honda
 * Naomasa Ii
 * Yasumasa Sakakibara
 * Ietsugu Sakai
 * Tadaoki Hosokawa
 * Nagamasa Kuroda
 * Masanori Fukushima
 * Hidetada Tokugawa
 * Terumasa Ikeda
 * Masanobu Honda
 * Takatora Todo
 * Kiyomasa Kato
 * Masamune Date
 * Kojuro Katakura
 * Yoshiaki Mogami
 * Toshitsune Maeda
 * Saizo Kani
 * Hideyasu Yuki
 * Takatomo Kyogoku
 * Tadanao Matsudaira
 * Tadayoshi Matsudaira
 * Toshitsune Maeda
 * Hirotaka Terasawa
 * Naotaka Ii
 * Tadatomo Honda
 * Yasukatsu Sakakibara
 * Yoshimasa Tanaka
 * Yoshikira Kato
 * Hirotaka Terasawa
 * Okatsu

West

 * Mitsunari Ishida
 * Sakon Shima
 * Yoshitsugu Otani
 * Hideie Ukita
 * Yukinaga Konishi
 * Yoshihiro Shimazu
 * Toyohisa Shimazu
 * Hideaki Kobayakawa
 * Hidemoto Mori
 * Hiroie Kikkawa
 * Ekei Ankokuji
 * Satoie Gamo
 * Morichika Chosokabe
 * Teruzumi Akashi
 * Masayuki Sanada
 * Yukimura Sanada
 * Josui Kuroda
 * Yoshinobu Satake
 * Muneshige Tachibana
 * Terumoto Mori
 * Katsunaga Mori
 * Shigenari Kimura
 * Matabe Goto
 * Masaie Natsuka
 * Naoshige Nabeshima
 * Harunaga Ono
 * Shigemoto Matsuno
 * Kagekatsu Uesugi
 * Kanetsugu Naoe
 * Keiji Maeda
 * Hideyori Toyotomi
 * Sasuke, Saizo, and Kosuke

Others

 * Lady Yodo
 * Garasha
 * Senhime

Battles

 * Skirmish at Kusegawa
 * Battle of Sekigahara
 * Escape from Minakuchi
 * Retreat from Ueda
 * Defense of Hakone
 * Battle of Harima
 * Defense at Seta
 * Battle at Mount Fuji
 * Summer Battle at Osaka
 * Winter Battle at Edo

Allusions

 * The monochrome painting of two samurai armies clashing for the game's Japanese cover can later be seen during the opening sequence for Samurai Warriors.
 * In the Japanese version of Kessen, Teruzumi Akashi performs an upbeat dance with his men before fighting the enemy. He had two different dances, depending on the unit type he has for his army. This was cut in the American port but is parodied by Meng Huo in the following title.