Aggressive!

From Aggressive Game Designs:

With Aggressive!, Players will enjoy high-res, 16-bit color at 30fps while blasting 99 different and unique alien ships through ten challenging levels. Players can use a joystick, gamepad, or keyboard to control thier ship while picking up powerups that upgrade their ship to 25 different combinations of firepower and armor. Aggressive! can be played on any PC compatible computer that has Microsoft DirectX(tm) 7 installed.
Aggressive features 100% 3D rendered artwork, big bad bosses and sub-bosses, and a radar screen that gives the player advance warning of the hordes of aliens sweeping down the screen.
Aggressive! comes with awesome sound effects, but no music. Instead, the player can customize which CD audio track gets played during different parts of the game. The player can put in his or her favorite music CD, select different tracks for different levels, and enjoy Aggressive! on a whole new level.
Aggressive! also has what many arcade games lack; extensive difficulty settings. Speed, Difficulty, and Intensity can all be adjusted from 1 to 10, allowing each player to tailor the challenge he or she faces.