Geist is a game that hasn't pleased everyone, but that doesn't meant it should be ignored.
To put it bluntly, your soul has been ripped from your body, and in your ghost form, you must make your way through the Volks complex in search of your physical form, all the while taking possession of objects, animals and many humans. Geist may be a first-person shooter, but it sports a lot of adventure and puzzle aspects into the gameplay.
When you first look at Geist, you may be disappointed by the medicore graphics, and there's no wrong in that. Unfortunately, the game features dated visuals, from the dull colors, to the lack of details in select places, and especially in the poor character designs. Some, like your buddy Bryson, are fine to look at, but others, such as the human form of the main character, John Raimi, and even the young Volks, look pretty bad. Textures aren't handled well, tones are weak, and they sometimes look like something out of a late-N64 or PSX game. This could be tolerated if it was an early game from 2001 or 2002, but since Geist came out in late 2005 on the Gamecube, there's no reason for the way the game looks.
And another thing that may get on your nerves; the framerate. While most of the animations in the game are rather well done, you will notice a slight slowdown during gun fights, or when there are simply a lot of NPCs performing actions. It's not a serious flaw, as you'll still be able to play fine, but it can get aggravating at times, and again, it shouldn't happen at this point in time on a system as strong as the Gamecube.
However, this isn't to say that everything looks bad. You won't find incredible realism anywhere, but some of the artstyles are pretty nice, and there's a lot of unique imagery. While traveling as your ghost, everything will look real odd; the colors are distorted, things move slowly, and the light is used to make a creepy effect. Even instances such as when you possess a computer, and see the images on the monitor backwards make for interesting experiences.
Sound-wise Geist does well. The music won't blow you away, but each tune fits the mood perfectly during the segment it's used for. The only problem is that it sounds a little muffled at times, as if the volume was turned down.
Sound-effects are nothing special, often sounding very generic, but what makes Geist a joy to listen to is the voice-acting. It may only be implemented during cutscenes, but it's pretty darn good. The sound quality of it is superb, the dialogue is smart and believable, and the voices themselves sound like they were straight out of an anime or a movie.
When it comes down to playing Geist, you may or may not be disappointed, depending on how high your expectations are. If you think this is Perfect Dark reborn, keep looking, because, frankly, the shooting portions of Geist are nothing to rejoice about. It's not that they're poor, in fact, the controls are very easy to use, but that they're simplistic; a bad kind of simplistic. The best way to say it is that it's nothing you've seen before. Luckily, the enemies are rather accurate, so you'll get a decent challenge from them during the shoot-outs.
Still, it's the possession mechanics that make Geist shine. You'll never find anything like it in any other game, and that's a fact. Geist lets you take control of certain objects and creatures in order to proceed through the complex, and you'll usually be able to do funny actions with the inanimate items. If you wish to take control of an animal or human, you must scare them, with requires you to act with another object. This may seem boring at first glance, but it only adds to the puzzles of the game, which, overall, are fun tasks to carry out.
The possession is especially enjoyable for certain boss-battles where you have to continually switch between characters and objects, and perform all different actions in order to combat the enemy.
Geist's story mode spans nine chapters, but you can probably beat it in six to eight hours. You'll find most of the value in the Multiplayer, which consists of three very fun modes; Death Match, Capture the Host, and Hunt. In multiplayer, you can play with up to four human players, and four computers, making for a populated experience. There are several levels to be unlocked, many of which come straight from the campaign, and in order to get these, you must find the Host Collectibles hidden throughout the Volks laboratory.
Overall, Geist is a solid game that could very well be your cup of tea. It certainly doesn't suit all video-game tastes, but if you're looking for a Mature Gamecube game, an interesting First-Person adventure, or a new way to play the FPS genre, Geist is highly recommended.