Ninja Gaiden II is the best game ever made and Sigma 2 is trash.
Razor's Edge is pretty good. Here's what I wrote about it elsewhere:
I'm impressed by how much they managed to improve NG3 (which is a terrible game), but RE is still far from perfect. Honestly, it's unfair to hold it to the standards set by NGB and NG2 because the guys responsible for those games are long gone. Essentially, this is a new team's first* attempt at Ninja Gaiden, and even though it's really good, it's still sloppy in comparison.
Most of RE's flaws are pretty minor, but they really start to add up after a while. The two biggest issues are the combat and the enemy AI. Maybe it's fair to say that it plays like a dumbed down Ninja Gaiden II. You usually don't have to think about which combos you use - once you understand the fundamentals, pretty much anything will work. There isn't much strategy to it, you can do whatever you feel like doing and most of the time, it'll be fine. You do have to change up your tactics for certain enemies, but it still doesn't have anywhere near NG2's level of depth. That's hardly a deal breaker, though. It's still very fun.
There's no excusing the obnoxious AI that some enemies have, though. Sometimes they'll just decide to block and evade all of your attacks, and there's practically nothing you can do about it. Maybe they thought players would praise how "smart" they are, but it just makes them really annoying to fight. While Team Ninja was busy copy+pasting as much as they could from NG2, they should have looked at that game's AI and figured out why it worked perfectly for it.
But of course, they made a lot of good changes to the game. Like I said, they lifted as much as they could from NG2: Enemies, bosses, the dismemberment system, ninpo, weapons, Tests of Valor, the shop/upgrade system, etc., and it all goes a long way towards saving NG3. They even had some good ideas of their own, like the Cicada Surge and the Steel on Bone mechanic. The SoB was in the original NG3, but it was pretty much broken. It works differently in RE. Enemies now have attacks (typically grabs) that make their hands glow red. You have to dodge one and counter with a heavy attack to start a SoB chain. In NG3, you just had to weaken an enemy, slide into him, and hit Y. There's some risk involved now, especially since grabs usually do insane damage on MN/UN. They also added a limit to how many enemies you can hit in one SoB chain (up to 4), so it's a nice improvement all around.
The Cicada Surge is interesting. It's a new counter (on LT+A) that teleports you behind whoever is attacking you, except you can use it at any point, even during the middle of a combo. It requires some ki and if you mistime it, you'll be vulnerable for a moment, so it's not a safe "I win" button. This lets you dodge hits that you'd normally have to take, like if you were to start attacking an enemy that suddenly does something with super armor, or if you're attacking one enemy, and another comes out of nowhere and tries to attack or grab you (NG3's AI does this all the time). To me, this mechanic goes against Ninja Gaiden's principles, but I think it works perfectly as a bandaid solution for this game in particular. That's because NG3 is much more ground-based than the previous games. Your combos are longer, enemies have more health than before, they dodge launchers constantly, and they're always trying to attack. The Cicada Surge is practically a necessity in this game.
I'm optimistic about Ninja Gaiden 4 now. Razor's Edge is basically Team Ninja's way of saying, "we know NG3 was shit, we're going back to what made the previous games great". They weren't completely successful, but at least they have the right idea now. If NG4 is built from the ground up with the right vision, it might even be great.
