I'll skip the story of how much Dungeons & Dragons has influenced my life and habits as I went into a good amount of detail in my review of the original Neverwinter Nights 2, but I will rave about how much I love a good story. Plot is the key to enjoyment in most games I play. I must feel invested in the characters and events to truly find myself immersed in the game. The original Neverwinter Nights 2 game did a fairly decent job of pulling me in and making me care about the events, but this first official expansion drew me in and wouldn't let go (much to my editor's dismay.)
The expansion is just that. It requires the original game to play and lets the player experience life in the epic 20- to 30-level range. If you've gone through the original campaign with your favorite character build, know that you can easily import him or her to this new game; or if you want to try out the new class and race options, you can create a fresh character and level them up to an appropriate level before adventuring.
The gist of the plot is that no matter what class or race you play, you remain the character from the original campaign. This means that having the experience of the first part will give you a little more understanding as to why you are there, though it isn't required for more than exposition and back story. Your character wakes up in a mystical "cell" in a cave, and the fancy silver shard that was the focus of the original campaign has been removed from your chest. This opens a sense of hunger in your character that, as you progress, develops into a soul-eating addiction. Now, that sounds a little strange, but I'll go into more depth a bit later.
Again, it is difficult to go too far in depth on the plot without ruining some of the joy of this game, but in general, you are trying to find out what happened to put you in this situation in this somewhat far-off part of the world. The other Neverwinter Nights titles took place primarily in the Sword Coast area of Faerun, but the designers have moved on from this area of the world and set this chapter in the far-off Rashemen. This setting ties in nicely to the focus of spirits and souls as the land is full of them.
None of the game mechanics were changed dramatically other than the inclusion of higher-level skills and the spirit meter. The meter is a means for keeping the player on their toes. There is a fine line when balancing your addiction - you must keep from wasting away or becoming more addicted to the souls to the point in which you need to consume greater amounts to get the same effect. While this idea is sound and the added benefits are decent, the mechanic of managing an addiction took a little bit away from the game.
The companions you meet and accompany you for your adventures are done fairly well and complement whatever choice you make for a character. Due to the darker feeling of the story in Mask of the Betrayer, you find that they are mostly a bit more "grown-up" than the characters from the original campaign or even the first Neverwinter Nights. The epic-level setting of the game and the more focused plot of this expansion lend themselves well to the more adult dialogue choices.
Graphically, the game is as good if not a bit better than the original campaign. Because your spells are so much higher level and the enemies a bit more outlandish, at times you will see the battlefield light up with amazing spell effects. The designers have done a great job at making the world look a bit darker and more surreal. to You find yourself in a shadowy version of the real world on occasion, which is almost a black and white picture.
Beyond the battles with tougher foes and spirits, you will be solving puzzles to solve to progress through the plot. These are a nice change of pace at times and allow you to truly think rather than hacking and slashing through every part of the game. Mix in some plot development, and you have a great unfolding story.
The only issue I really had with the game, beyond the somewhat distracting spirit meter, is that the camera would not behave consistently. I found myself fussing camera alignment more than I should have or cared to. But even this minor detraction couldn't mara game that keeps you involved in a developing plotline. The expansion is more than worth it. The additional pieces of the toolset based on the newly designed areas in the game will be a great addition to any mod creator's arsenal, and the ability to make the new classes and races in the original campaign will keep those who love to replay the game interested. I highly recommend the expansion for those who own the original and want something more to try.