Gore, guts, and swords. Ninja Gaiden 2 has flaws, but in the end they can be overlooked.
As far as shortcomings, Ninja Gaiden 2 has a few, but they are generally overshadowed by the beauty of the rest of the game. The camera still sucks, I'm not going to be nice with that, a major company such as Team Ninja should know better after all of these years, and the environments look awfully "shiny" compared to real life. Plus, there is this weird "layer" between the walls and the blood of the other ninjas. It almost levitates in mid-air.
Ninja Gaiden 2 is a frustratingly game (as it should be). It is more gruesome and gory than its predecessors. This only makes it more enjoyable in an odd sadistic way. For any die-hard fan of the series, Ninja Gaiden 2 is a must buy. For the rest of you, you should still probably check it out.