Os jogos Ninja Gaiden estão no mesmo universo?

De acordo com o criador do jogo, Tomonobu Itagaki, os jogos no universo Ninja Gaiden (os dois novos jogos e a Trilogia NES anterior) formam uma história contínua e única

VideoGamer.com: We've read that this is the last chapter in the Ninja Gaiden saga. Is there any truth to that?

TI: I really put all my heart and soul into making this the definitive game in the Ninja Gaiden franchise. So I personally don't intend to make any more. This is a game we basically built from the ground up. We threw away everything we had from the first game, improved on what was good, changed what was bad. So it's been a long project, it's been close to three years in the making. We were able to accomplish everything that we wanted to achieve with this franchise.

In story chronology as well, this takes place after the first Ninja Gaiden for Xbox and then after, the story of this game it leads into the old NES ones, so I think we have a nice continuity there.

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Obviamente, isso não leva em conta alguma descontinuidade canônica, mas isso pode ser atribuído a erros de produção.

Oficialmente, eles estão na mesma continuidade que os jogos NES com os jogos XBox operando como prequels.

his continuity has been reworked to tie the classic Ninja Gaiden and current Ninja Gaiden titles together in the style of games such as Metal Gear and Metroid that rework their continuity to tie their current titles with their classic titles. Minor changes would have to occur such as character appearances and Jô Hayabusa would have to go by his name in the Japanese version Jô Hayabusa. This is done for those who want to see how they fit together, otherwise omit the classic Ninja Gaiden games in this timeline for a more simple continuity. Officially the continuities are tied together