Samurai Showdown, also known as Samurai Spirits in Japan, was a big hit for the Neo-Geo gaming console back in the 16-bit era, mostly due to its innovative weapon-based combat, detailed, animated backgrounds, and larger-than-average battlefields. When localized, the game suffered from a poor translation, rife with typos and odd quirks. For example, both Tam-Tam and Earthquake say that they will crush their opponents with their spears, despite the fact that Tam-Tam clearly uses a sword and Earthquake a kusarigama (a sickle attached to a chain). Amakusa also claims to be working for "the dark guy" whenever he first meets a character.
Players face each other one-on-one, in a 2D field that can be enlarged if the fighters are far enough from each other. Unlike other fighters, however, each character fights with a weapon, ranging from swords (in fact, most characters use swords) to spears. They can also use physical attacks (there are strong/weak attack buttons for both weapons and physical attacks), but this rarely comes up. The weapons increase the range of characters' regular attacks, and if both characters attack in a precise way, they can lock weapons. When they lock weapons, each player must rapidly press buttons to win the standstill; the loser drops their weapon, while a tie results in both players losing their weapons.
Also unlike other fighters, the game featured items. They included treasure (points), food (healing), and bombs (damage). A running referee would toss them into the arena at random intervals. In addition, a referee would hold up a flag whenever one of the players took a hit; he would hold up a different colored flag depending on who got hit. This referee, named Kuroko, would become a hidden character in the Game Boy port, using his flags as weapons.
Samurai Shodown also featured mini-games at regular intervals throughout the single-player mode. Players had to slash through ten straw men in the span of thirty seconds. Straw men would only stay up for a short amount of time, this amount of time lessening in later iterations of the mini-game. For the most part, cutscenes took place immediately before and after the mini-game, showing Amakusa's rise to power and his revenge against the Tokugawa. There were only two exceptions, one of them being the ending for a particular character's story.
Note: this only covers characters present in the original arcade version.
The main villain of the first Samurai Shodown game and several games afterward, Amakusa wishes to destroy the Tokugawa and gain great magical power. Unfortunately, he is not a playable character. Amakusa has one of the widest movesets in the game, being able to launch himself like a meteor, create a boomerang-esque ball of magic energy, teleport around the stage several times, and punch at his opponents rapidly.
A green devil, Gen-An can rush at his opponents as a spinning blade-ball, climbing the wall he hits to come back down and hit them again. Gen-An can also send a ball of poison gas at his opponents, potentially disabling them temporarily if it hits. He fights his enemies with a giant steel claw he wears on his right hand.
A San Francisco swordsman, Galford is one of two characters in the game to get assistance from an animal: his dog, Poppy. Poppy is most likely a girl, since the credits reveal that she has puppies. Like Hanzo, Galford can launch projectiles at his opponents, create holograms of himself to confuse his enemies, and disappear to strike from above. He can also send Poppy to maul other fighters.
Like Hanzo, Jubei is based on a famous historical figure; in this case, he is a legendary samurai. His moveset includes multiple stabs, followed by an uppercut similar to Charlotte's, and sending a shockwave along the ground to his enemies. Jubei insists that he is not that guy from Fatal Fury.
A blue-haired swordsman from Japan. Ukyo can send a fire bird down while jumping, and repeatedly slash at his opponent. He signals the latter by throwing an apple, which he rapidly slashes, as well.
A French knight, Charlotte is one of two female characters in Samurai Shodown. She is sensitive about this fact, telling opponents not to mention her plate (most likely her breast plate). After defeating Amakusa, Charlotte returns to France to aid the peasants in the French Revolution. She can perform a triangle slash, drag a green column up with her while jumping, and charge at her opponents with multiple sword thrusts.
A Mayan warrior always seen wearing a mask. Oddly enough, he is one of the few characters with any stake in what Amakusa is doing; after beating him, he takes the orb that Amakusa used as a weapon. This orb apparently belongs to the Mayans, and Tam-Tam uses it to heal the ailments of those around him. Tam-Tam can throw skulls, summon rising demons, and spin his flaming sword while moving toward his opponent.
Based in Texas, Earthquake is the leader of a gang of thieves searching for treasure. In fact, upon defeating Amakusa, his three subordinates return to him with piles of treasure. He is tall, fat, and missing several teeth. Earthquake can rush toward his opponent as a spinning blade ball, or bounce toward them to harm them with his butt.
An Ainu priestess, Nakoruru is not only one of the two female characters in the first Samurai Shodown, but also one of two characters who fight with animal friends. Her hawk, Mamahaha, can lift Nakoruru into the air, allowing her to drop down and slash her opponent. She can also rush toward her opponent, either remaining on the ground or rising up to do so.
The King of China, Wan-Fu is the only character who can voluntarily give up their weapon. This is done by jumping into the air and tossing a flaming sword at the opponent. Usually, when the AI does this, they run toward the sword to retrieve it. Wan-Fu can also perform an uppercut with his sword.
The protagonist of the Samurai Shodown series, Haohmaru is a Japanese swordsman. His moves include sending a tornado at enemies and a type of sword uppercut. After his fight with Amakusa, Haohmaru returns to Japan and fights Mai Shiranui of King of Fighters fame.
A Tokugawa ninja based on a historical figure. He can send fire toward his opponents, throw shurikens, and disappear to strike from above. After defeating Amakusa, Hanzo spends his life training other ninjas.
A kabuki actor, Kyoshiro can toss flaming fans, spin-jump at his opponents, and use his poll to thrust himself at the opponent as a fireball.
After being made for the Neo Geo, Samurai Shodown was ported to many systems. However, few were capable of running the game at the technical level that the Neo Geo did. For example, the SNES, Genesis, and Sega CD versions removed the scaling present in the original; instead, they kept the characters at a constant size (the Genesis and Sega CD used the large sprites, the SNES their small counterparts). The SNES and Genesis versions also removed the blood present in the original. The port closest to the original was the 3DO version, which kept the scaling and blood that the others lacked.
In addition to a playable Amakusa, the Game Boy version had two additional unlockable characters: Kuroko, the referee, and Hikyaku, the courier man that throws item onto the battlefield. Although Kuroko would also become a playable character in later games, Hikyaku has yet to resurface in that role.
Samurai Shodown would also appear in later compilations alongside other Samurai Shodown games. It was ported to the PS1 along with its sequel under the name Samurai Spirits Kenkaku Shinan Pack. However, this port was only available in Japan. However, it would also appear in Samurai Shodown Anthology for the Wii, PS2 and PSP, along with its five direct sequels.
Samurai Shodown, along with II and III, were also ported to the Wii's Virtual Console. All three were ports of their Neo Geo incarnations, making it unlikely that the SNES and Genesis ports of the game will be ported, as well.