Was there ever bad guys?

The zerg dont believe that theres anything wrong with what they are doing. there is also no discontent in the zerg swarm. this is because they are 1 mind. But without that singular controlling thought, they are simple animals.

So if the overmind was evil, the zerg become evil. BC the zerg are controlled by kerrigan, who is a twisted and evil wench, the broods are twisted and evil.

 

the overmind is also trying to make his race survive by evolving Kerigan herself is the closest to evil and thus her broods.
if you could ask the Quel guys whos evil what would they say ???

 

Everyone, every factions in the SC1 story are fighting for their own benefits and survival. It all really depends on which perspective you're coming from. Also because the player have played as part of most of the factions, we really don't have inclinations towards who is the bad guy.

Afterall the story is great isn't it?