I had the same impression as Skyblade about how and why the Weapons are about and acting in the way that they are, namely that they were to eliminate threats but as Sephiroth was unreachable, they just went on a general rampage and went after Mako reactors.

Quote Originally Posted by Raistlin View Post
If you want to get technical, don't you only need a green? :p

The Weapons were summoned in response to Meteor. I always thought that they just went a little crazy because they couldn't really do anything about Meteor. Only two Weapons actually attacked population centers, and one of those places (Mideel) didn't even have a Reactor.
In my head, I imagined that it went to Mideel because of the access point to the Lifestream and its abundance of Mako energy, but that was just a conclusion I jumped to.