Graphically, the game is everything you remember about the golden days of gaming. There are no lighting effects or 'pixel render cel-shading', or any of the other buzzwords people like to throw around these days, it's all about simplicity - and it works. I'm talking about fireballs that blink red-to-orange to show they're hot, and ninja throwing stars that magically power-up to become blue flashes to show they're powerful. Bullets the size of your character's forearm, characters who run through the same 2-3 animation cycles and level designs that have you scratching your head as to how this can be a functioning building - you name it, and you can probably find it. Sure, someone who was brought up on the PSX and that new-fangled 3D might say the game looks like crap, but this is how gaming was done in the past and it works.
As much as I liked the graphical style, I did find a few flaws that marred an otherwise neat retro experience. For one, the ninja's walking animation is terrible. I know the art guys where trying to portray the cool ninja stealth movement, but the 'I couldn't find any more toilet paper tip-toe' really doesn't work all that well in getting that point across.
The sounds are passable and work, but didn't have quite the same effect the graphics did on me.