I'm confident that Ninja Gaiden Sigma is one of the greatest action games ever made. Sure, it's a re-release of a re-release, but it's such a well-balanced and content-heavy title that its easy to overlook whatever flaws may, may not, and possibly do not exist. Last year's Xbox 360 exclusive Ninja Gaiden II probably holds the record for videogame brutality, but it unfortunately doesn't measure up to its predecessor in any other way. Ninja Gaiden Sigma 2's goal is to solve many of those problems, while adding a ton of new content. It's not as good as Ninja Gaiden Sigma, but make no mistake: this is the best version of Ninja Gaiden II.

Ninja Gaiden II is one of the bloodiest action games ever made. Because of a design decision we may never understand or forgive, Ninja Gaiden Sigma 2 is, by comparison, nearly bloodless. It takes the viscera out of all the evisceration. The action is as intense as ever, but I can't honestly say it's quite as satisfying. Every dismemberment and decapitation is accompanied by a jet of flame and a very small spatter of blood. I guess that's supposed to represent the evil that has infested the bodies of all the Fiends and Black Spider clansmen, but I'm not buying it. Violence aside, Sigma 2 is a better-looking version of Ninja Gaiden II. Some of the environments are still a bit on the bland side, but it's okay, since your eyes will be focused mainly on the outstanding character designs and animations.

You have the option of using either the English or Japanese voice track, and I strongly recommend going with the Japanese track. The voicework for the English track is pretty bad, even when taking into account that the dialogue is beyond redemption. Plus, if you use the Japanese track, every extremely powerful attack is announced with a savage "HWAAAAGH!" instead of a "Ya!" or a "Hoooh!" The music is decent, as well. It won't send you into a bloodthirsty rage like it probably should, but it's nothing you'll hear in an elevator.

Ninja Gaiden Sigma 2's story is a pretentious, unintelligible excuse for Ryu Hayabusa to flip out and kill legions of Fiends and enemy clansmen. When a mysterious organization razes the Hayabusa Ninja Village and steals a precious artifact, Ryu Hayabusa (quite possibly the gaming world's most powerful character) finds himself on a quest to halt the resurrection of the all-powerful Arch-Fiend. By doing all of this, he will get vengeance... again. If you feel like you've just lost a few brain cells from reading that, know that the story definitely takes a back seat to all the over-the-top action; in fact, consider the story to be in the trunk.

The modern entries in the Ninja Gaiden series are action games in the vein of titles like God of War -- although, technically, the original NG came first. You move from area to area, killing enemies and solving environmental puzzles. Ninja Gaiden games differ from other action games when it comes to combat design. In several other action games, you learn a number of basic combos that you'll use for the majority of the game. Not so with a Ninja Gaiden game, much less Ninja Gaiden Sigma 2. Each button combination is something you'd see out of a complex fighting game; given Team Ninja's reputation, that should come to nobody's surprise. Simply pressing buttons will rarely get the job done. You'll need to hold a button for a half-second before continuing a certain combo. Other times, a flick of the Left Analog Stick will be the difference between a ground combo and an aerial one. If you think that's deep, I haven't even thrown Ryu's amazing agility into the mix. Not only can he run along walls for about twenty feet -- he can sprint on the surface of water. Oh, I didn't mention that he can also use Ninpo: offensive magic that allows him to immolate his foes or slice them to ribbons with blades of air. My favorite Ninpo is the Art of the Piercing Void, which allows Ryu to conjure a ball of pure emptiness and hurl it at whatever's unlucky enough to be in his way.

Ninja Gaiden 2 is famous for being one of the bloodiest games of all time, but it is also infamous for being one of the most difficult. Tomonobu Itagaki (the former head of Team Ninja) once famously remarked: "The enemies in other games are there for you to kill. In Ninja Gaiden, they're there to kill you." He's right on the money, and nobody could have said it better. This game is full of enemies who mean to do you in, and they're always armed with the tools and talent to do it.

Ninja Gaiden Sigma 2 is a lightning-fast action game that emphasizes defense and improvisation above everything else. As a result, it's one of the most satisfying action games out there. As I mentioned, it's a game with several offensive and defensive mechanics; if you want to succeed, you'll have to make great use of both. If you don't, you'll be seeing the Game Over screen much more than you'd like.

Several of Ninja Gaiden II's enemy encounters and boss battles are cheap, and some of them are unreasonably so. Sigma 2 gets rid of some of the annoyances, but it also forces you to fight new bosses -- like the Statue of Liberty. Yes, Lady Liberty herself has been possessed by the Greater Fiend Alexei, and she'll murder you by blasting you with lightning. Oh yes, this is a Ninja Gaiden game through and through.

The world of Ninja Gaiden contains nary a modestly-endowed woman. In Ninja Gaiden Sigma 2, you'll be able to control not one, not two, but three buxom killing machines. If you made your mark on the Holy Vigoor Empire in Ninja Gaiden Sigma, you were able to play as Rachel, the blonde with a ridiculously large... warhammer. She makes a return appearance. As I mentioned, there are two newcomers. The naginata-wielding shrine maiden Momiji was introduced in the DS-exclusive Ninja Gaiden Dragon Sword, and she's got some interesting abilities, such as the Aerial Ultimate Technique. The second (and perhaps the most well-known) newcomer is the purple-haired kunoichi Ayane, who has been a part of Team Ninja's Dead or Alive series since its inception. The new characters are great fun to play as, and they also pave the way for Sigma 2's single best addition: multiplayer.

You read it right: Ninja Gaiden Sigma 2 features a cooperative mission mode, in which you can slaughter your foes with a buddy. It's a joy to show off in front of your co-op partner, but more often than not, it feels like a race to see who can get to the next unlucky contestant. Playing the game solo makes you feel like a veritable force of destruction. Playing it cooperatively... well, you get the idea.

If you don't mind spending a little extra for your copy of Ninja Gaiden Sigma 2, you'll be rewarded with the game's soundtrack and a graphic novel. Some of this graphic novel is actually presented during the initial game install, but there's a lot more in the book itself. The art is great, but the story registers a solid "Ah-hyuck!" on the Goofy scale. Overall, the collector's edition is the one for the hardcore players. If you don't think it would interest you, you're probably better off with the standard edition.

If you've already got Ninja Gaiden II, you should still consider a purchase of Ninja Gaiden Sigma 2. It offers enough new quality content to be considered a step up from the original, and the multiplayer is immensely satisfying. If you haven't played a Ninja Gaiden game in your life, go pick up Ninja Gaiden Sigma and Ninja Gaiden Sigma 2. We'll wait.