Stay alive long enough for the screen to accumulate 20 baddies - then zap 'em!
Have 30 smarts in hand at standard difficulty level or higher
Complete the first 60 waves in a single game
Finish wave 20 without touching a mine or other obstacle at standard difficulty level or higher
Score 25,000,000 points or more in one game
Complete the first wave in 5 seconds
Reach 5,000,000 without using a single smart bomb
Reach 3,000,000 points without losing a life at standard difficulty level or higher
Score 250,000 points or more in one game at standard difficulty level or lower
Collect 30 or more bonus crystals in a single game
Score 250,000,000 points or more in one game
Have 30 lives in hand at standard difficulty level or higher