I think they're more a force of nature or weapon that got out of control. They're also similar to the Borg in ST or replicators from Stargate. Maybe you don't

I think they're more a force of nature or weapon that got out of control. They're also similar to the Borg in ST or replicators from Stargate. Maybe you don't consider those to be evil, but they're certainly bad, like cancer is bad to an organism.