Score 1,000,000 million points during the Campaign (any difficulty, any speed) or Score Tilt mode.
Along with this achievement are some higher tiered achievements for score:
If you follow these simple rules when playing you should have no problem soaring past 30 million points:
-Keep your ships spread out as often as you can, this increases your score multiplier on anything that you kill.
-Use your shield to kill enemies! In conjunction with your ships spread killing enemies with your shield yields even more points, especially on the bigger enemies.
Personally I nailed all these score achievements on my Normal run through and soared past 30 million. I simply kept my ship spread in a small circle most of the time and used my shield on enemies of all sizes, especially the large ones. Many times I could get 100's of thousands of points from one large enemy.