Tyrian

The Good
The sheer amount of variation - each level seems to have its own graphics and style * The amount of customisations that can be made - from weapons to game play modes

The Bad
You can get into some very hard hidden levels near the start of the game - near instant death.

The Bottom Line
One of the PC's best shooters. Varied graphics plus a huge range of weapons and other enhancements make this a game to play over and over again.