This is a great game, which is best described as an action-adventure/stealth game. It is an action-adventure in the Zelda vein. The unique aspects of this game include the multiple ways one can get past certain areas and the AI partners whom work well and are put to good use in this game. The game has great puzzles and story as well. In this game you will fight aliens, solve puzzles, sneak past aliens, take pictures of enemy intel, take pictures of endangered species, and explore a rich (though admittedly not vast) world. The only flaw in this game is that for the type of game this is, it is somewhat short.
