Tenchu

Tenchu
Genres	Action-adventure, stealth
Developers	Acquire, K2 LLC, FromSoftware
Publishers	Sony Music Entertainment, Activision, From Software, Sega, Nintendo, Microsoft Game Studios, Ubisoft
Platforms	PlayStation, PlayStation 2, Xbox, PlayStation Portable, Nintendo DS, Xbox 360, Wii
Platform of origin	PlayStation
First release	Tenchu: Stealth Assassins February 26, 1998
Latest release	Tenchu: Shadow Assassins February, 2009

Tenchu (天誅) is an action-adventure stealth video game series, originally developed by Japanese developer Acquire, where the player assumes the role of a ninja in 16th century Japan. The title in Japanese literally translates in English as: "Divine Retribution", with 天 (ten), meaning heaven and 誅 (chu), meaning death penalty (another translation of this phrase, Wrath of Heaven is the title of the first PlayStation 2 entry in the series).

The series takes place in 16th-century feudal Japan. The original story (Stealth Assassins) revolves around two ninjas, Rikimaru and Ayame, who have both been members of the Azuma ninja clan since childhood. The two ninjas serve the benevolent Lord Gohda and work for him as his secret spies to root out corruption and gather intelligence in his province. However, the evil demonic sorcerer Lord Mei-Oh sought to destroy Lord Gohda, and using his demon warrior Onikage, wreaked havoc throughout Lord Gohda's province. Although Mei-Oh was killed in the first game, Onikage appeared in all subsequent games (except Fatal Shadows and Tenchu Z) as the archenemy of the two ninja, especially Rikimaru. Another major character who shows up frequently is Princess Kiku, Lord Gohda's daughter who often needs to be saved.

The game perspective is third-person. There are numerous items to help the ninja on his/her mission, but unlockable items can be acquired if the player gets a "Grand Master" rating at the end of the level by being as stealthy as possible. Items and controls vary from game to game, but the gameplay is essentially the same throughout with the exception of Tenchu: Shadow Assassins. Stealth is a very important element in the game, where players have to duck, crouch, and hide behind walls to avoid detection. Enemies can be killed with one manoeuvre by using Stealth Kills, and a player can avoid detection by using the Ki meter. The larger the number, the closer the player's position to an enemy. If a player is spotted, the Ki meter will turn red, the enemy will alert everyone in the area, and the player is forced to fight hand-to-hand or hide somewhere until the enemies give up their search and resume their patrol routes.

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Wikipedia