Dead or Alive 4 (Japanese: デッドオアアライブ4, Hepburn: Deddo oa Araibu Fō, abbreviated as DOA4) is a 2005 fighting game developed by Team Ninja and published by Tecmo for the Xbox 360. It is the fourth main entry in the Dead or Alive fighting series. The story of the game focuses on the continuing war between the Mugen Tenshin Ninja Clan and DOATEC, and Helena Douglas taking over the mantle of DOATEC as its new president, determined to fight against the corruption within the enormous organization. The game's story mode introduces the player to new characters and opponents via combat which can then be played in the game's other modes. New features are introduced in the gameplay and the game's online mode. Dead or Alive 4 was generally well received, with an average score of 85/100 on Metacritic. By mid-2006, the game sold over 1 million copies worldwide.[1] On November 15, 2021, Dead or Alive 4 was made available on Xbox One and Xbox Series X/S through backward compatibility.[2] The game was later followed by Dead or Alive: Dimensions in 2011 and Dead or Alive 5 in 2012.