This game brought great pain to my soul.
So if you explain it like this: "A game with multiple ways of travel, such as top down, helicopter, and fps, with a multitude of different enemies that require different tactics to defeat." It doesn't sound so bad.
Then you actually play it. All this game was, was a poor attempt at some zombie apocalypse scenario. The game play consists of spam clicking something until it disintegrates into red paste. The art, even for 2001, was terrible, and the audio was so shrill my eardrums are bleeding. I regret playing this garbage.