Wow. It really felt like the movie character. Immersive.
Amazing environments. Graphics fit perfectly.
Voice acting. I can't even describe it. Its perfect.
Hand to hand. If you ever watched the movies, you know Riddick is a killing machine with his hands. It carries over to the game perfectly. Unlike most FPS that tack on hand to hand, they got it right in this one. You can break a neck, grab a guy who has a rifle and force it back and boom.
Sneaking/Stealth. Its just cool.
Atmosphere. There is one part in the beginning where you are in dark tunnels fighting guys with shotguns with flashlights and laser sights. Wow.
The bad? Ummm...errrr... Well, some of the characters seems to have lower detail textures. Thats the worst I got.
Amazing game. I highly recommend it.