Why did David kill the engineer population?
So why did David kill all the men and women Engineers anyway?
sharetoward the end David tells Walter '' serve in heaven or reign in hell? ''
so he has the desire to be emperor or dictator, he can do this through creating those perfect invincible aliens, however it's turning in circle with the question that so many people asked and no one can answer, since he is a robot why does he have those kinds of feelings and desires of domination, power and wealth; in theory he is only programed to serve and help the human his creators.