In 2006, Tecmo and Sony announced the development of Ninja Gaiden Sigma for the PlayStation 3.Eidos obtained the European publishing rights for this game. Tomonobu Itagaki had no direct role in Sigma, and judged it a flawed game, although he acknowledged that Sigma gave PlayStation owners a taste of Ninja Gaiden.
The Cell processor of the PlayStation 3 gave Team Ninja the opportunity to overhaul the game graphics to use larger and more detailedtextures. Changes were made to the game world, with a few new areas and several additional save points and shops, and alterations to the game engine let players shoot arrows in mid-air, fight on water surfaces, and play as Rachel in some chapters and missions.Team Ninja added more enemies such as bikers, fish-men, and a new boss, Gamov, and Ryu's weapon choices are extended with a pair of katanas called the Dragon's Claw and Tiger's Fang.
In 2007, Tecmo released a demo and a new game mode, Survival Mode, for Sigma over the PlayStation Network. The demo limits players to the first chapter of the game, but lets them play as Rachel in a separate mission. Survival Mode comprises missions in which players keep fighting until they have either killed all their opponents, or their character has been defeated.