The hands-down best game of it's genre.
Eternal Darkness goes to great lengths to not only create a spooky game atmosphere, but to actually try to directly disturb the player. Along with a health & magic meter, your character has a sanity meter. If you let that get low, I won't spoil what happens, but just know that some weird things happen. Expect the unexpected, this really is a game like no other.
This game is nearly flawless in every way. The visuals are great. The characters look good, and you often return to the same areas of the game hundres of years later, and you can see that amount of detail that was put into representing different time periods. The sounds are some of the best points of the game. The voice acting is excellent, and the spooky sounds and "sanity effects" are perfectly done.
The gameplay is great, even though this game isn't necessarily combat focused. The guns are okay, but the melee weapons are actually more effective, and much more entertaining. Lopping off the head of a zombie, and seeing it feel around where it's head was in a "what the..." type of gesture is very gratifying. There are also several magic spells that you learn throughout the game. I wasn't too sure about this to begin with, but they didn't overdo it with the magic.
The replayability is also pretty good for the game. The game takes several hours to begin with. But if you want to keep playing after the "end", or you're not satisfied with the basic ending, you can play through 2 more times for the "true" finale.
The only thing I wasn't crazy about was the camera angles, at certain points. There were only a couple times when I couldn't see an enemy that was pretty much standing right next to me. This wouldn't be so bad, but it makes me wonder why the C-stick couldn't be used to control the camera, since that stick wasn't used at all in the game. This isn't that big of a deal though, because usually the camera is right where it needs to be.
I'm not sure if this game deserves a perfect 10. But, it definitely fits in between a 9.5 and 10. And since I can only give it one or the other, I'll go with the 10. If you have a GC, this is a must have.