Ninja Gaiden II was great, but it wasn't on the level of Ninja Gaiden--and in the same way, Ninja Gaiden Sigma 2 doesn't quite reach the heights of Ninja Gaiden Sigma. But thanks to its heady new co-op missions, it comes awfully close. Forget any worries you had about diminished blood and embrace the fury that the game's comely trio brings to the table. Taking control of one of them while slashing up fiends with a friend is a total riot, as is guiding them through their single-player levels. Ninja Gaiden Sigma 2 may not have addressed every shortcoming of its Xbox 360 predecessor, but it does a great job of making up for them with raw, unparalleled swordplay.