 Players can select the degree of starting difficulty any time a new game is started . The initial level chosen is a value between zero and twenty that determines the number of viruses to clear , and the three game speed options change how fast the capsules fall in the bottle . The player 's score is based solely on the elimination of viruses , not on the time taken to complete the level or the number of capsules used . If players complete the highest difficulty level , they can continue playing to accumulate a higher score , but the number of viruses to clear remains the same . Additional points are awarded when multiple viruses are eliminated at once , but no additional points are awarded for initiating chain reactions , in which the elimination of one set of objects triggers the elimination of another set . The game speed is also a factor in how the game calculates scoring ; higher speed levels yield more points . 
