Team Ninja has added all sorts of goodness for the new (and cheaper than the original Xbox Ninja Gaiden) Ninja Gaiden Black. The original game is intact with some extra features and even the original ninja gaiden arcade game from the late 80s. The original arcade is nice and all, just don't expect to beat this one before your 80th birthday.
As for the main gameplay modes of Ninja Gaiden Black, we were certainly alarmed to find many aspects of the game even more difficult than we remembered. It's as if Team Ninja, Tecmo's internal development team responsible for this painful experience, is deliberately going out of its way to push the bar farther and farther toward the realm of impossibility.