Use the mouse to aim and fire.
Click and hold to increase shot's power.
Try to bring down as much gems as you can using maximum 5 shots per level.
Each collected gem gives you +1 point.
Earn level's minimum score (or more) to complete level. Less spended shots gives you more score per level.
Avoid bad gems with skull mark (-1 point).
Complete all 20 levels to submit total score.