
Originally Posted by
Rezildur
Here's what I think happened:
Overmind had no free will. So he made Kerrigan. Problem was, she was still infested with all that Zerg DNA which continued to make her act like an aggressive bitch -- just as the Overmind was.
The difference between the Overmind and Kerrigan is this: If they had used the Artifact on the Overmind it would have killed him -- just like it killed all of those other Zerg. Kerrigan is different, because she is part human, and so it probably neutralized whatever aggressive directive had been programmed into altering the Overmind and the Zerg.
Now, she is still a major psionic entity and still has some tie to the Zerg, so she has the ability to lead them freely without being a bitch, and accomplish something alongside the Protoss and the Terrans.