I know I would give it an 8.5, here are my complaints which I already posted:
I'm not enjoying Ninja Gaiden 2 as much as I would have thought, I really like the combat and fighting against multiple enemy's but the bosses just piss me off, it's not about skill but more about luck against them, usually they have a super annoying attack which makes you loose half of your health and you cannot evade it. So to beat them you have to be lucky and hope they don't use it too fast or too much. besides that the framerates often drop and the loading times aren't the best I've seen either, while graphics aren't really good either, yes the splatter effects are amazing, and the animation is one of the best I've ever seen, but there just not much detail in the backgrounds and they look kinda empty, still defiantly an 8+ game, but I think I agree with the reviewers that it's not an 9+ game. A well Ninja Gaiden: black just raised the bar too much I guess.
LOL I just beat the fourth boss without even trying just doing the up slice the whole time and his regular attacks can't hit you, next to that it does a lot of damage.
I wish there was a game which combines the boss fights and the cutscenes and story from devil may cry, and that the rest is coming from ninja gaiden, (the fighting system and the AI).
BTW I'm still agreeing with myself I'm now on the 7th level.
