Even by the standards of the Metal Gear franchise, this game is BOLD. Gone (for the most part) are the stealth aspects that defined every significant title in the series. Familiar faces such as Otacon, Colonel Campbell, Big Boss or anyone named Snake are nowhere to be seen. And while the typical military base and lab environments may still be seen, you'll be spending far more time fighting in massive cityscapes. There are some recurring elements (the requisite team of superpowered wackos is here, along with cardboard boxes and overlong codec calls), but the innovation deserves points.
The most interesting departure, however, is Raiden's complete inability to do a pacifist run the first time through. The game that introduced him made that a series staple, but now he doesn't have the means or the incentive to do so, and as the story progresses, he loses the will as well. You have to kill if you want to recover health and energy effectively, and Raiden's characterization reflects that. At times, it even got to the point where it seemed like I was listening to a Murder Simulators
message, but the game is fortunately subtle about it.
The gameplay, of course, is glorious. Raiden's movements are fluid, fast and flashy, making every kill feel satisfying. The action is terribly fast paced, but the controls are responsive enough to accommodate this. Parrying is difficult to master, but well worth it. There's decent weapon and enemy variety, so the game doesn't get stale as it progresses. And the boss fights couldn't be more perfect, each one being challenging, huge in scale and/or concept and an overall joy to slice up. The only issues I really have are that the camera isn't cooperative at times (don't ever get backed into a corner), and that the stun mechanic is awful. Violently wagging the control stick to escape isn't just annoying, it's potentially damaging to the controller.
The game looks and sounds as metal as its title. Bits of defeated enemies flying everywhere, waves of blue coming off Raiden's sword and explosions all get me pumped and also fail to clutter the screen or cause any slowdown. And as about half the soundtrack is outright metal songs with vocals, there will be no shortage of adrenaline.
Buy this game. It succeeds in everything it tries to do and then some. You won't be disappointed.