Bloody, action packed and maddeningly difficult, Ninja Gaiden Sigma adds a true gem to the PlayStation 3's beleaguered library, plunging gamers into a gorgeous adventure full of monsters, mesmerizing acrobatics and sweet ninja weapons. Former players will recognize Sigma as a port of publisher Tecmo's Xbox offerings, Ninja Gaiden and Ninja Gaiden Black, and the decision to drop $59.99 on it depends on whether they want to experience one of the coolest video games ever made. Again.

Much like its cousins, Sigma lets players control Ryu Hayabusa, the ninja assassin out for revenge against the mysterious forces that decimated his village. To combat his human and demonic foes, players execute a series of beautifully animated acrobatics, flipping Ryu through the air, zipping along walls and running up cliffs. In addition, they master a series of deadly ninja weapons, such toys as the Dragon Sword, a bow and Sigma's new addition, Dragon's Claw & Tiger's Fang and dual Japanese swords. They can also harness ninja magic, Ninpo, as well as level up and purchase equipment at Muramasa's Weapons and Tools shop.

Throughout the course of the adventure, Ryu travels to several exotic locations, engaging enemies in a dojo, battling them in a burning village and slaughtering bad guys on an airship. The action moves at a brisk pace, with scores of enemies assaulting him almost all of the time. This, while entertaining to a degree, stands out as one of the game's faults, as bad guys constantly re-spawn at the same locations. This proves especially frustrating when players accidentally leave a room while mashing the attack buttons. Thanks to the game's obscene difficulty, one mistake carries deadly consequences.

Tecmo also deserves a slap on its wrist for not improving the in-game camera angle. Gamers manually control it with the right analog stick, but despite this freedom, it manages to display awkward angles, allowing off-screen enemies to score some cheap shots.

Furthermore, the game lacks a user-friendly navigation system, thus causing players to wander in and out of the same locations and enemies re-spawn at will. As a result, gamers waste time battling the same adversaries, using up all of their health elixirs and eventually dying.