I figured you can destroy frontier outposts because colonized planets generate border themselves, that was a decent + back to my influence... thanks game for telling me that
Yes you can destroy frontier outposts
in my current MP game I was at war with a divine mandate insectoid, he had a controlled system just neighbouring my capital system. His was far from any of his planets so he had a frontier outpost here to be able to build all the mines he had. When I destroyed his frontier outpost, the influence from my capital spilled over here and I instantly took control of all his sexy mines
I then proceeded to invade his homeland but got wiped because I am a noob (I thought I could "kite" his army out of his spaceport range, got pulled in and quickly destroyed), but he had not much left himself so I was gonna fuck him good. He then formed a federation with someone else and my war was over, damn it.
I'm a mamal collectivist xenophobe, I want to enslave shit but I dont know if I should enslave my own kind? I still didnt have the necessary opportunities to enslave others. If someone is good at enslaving mechanics I would really love to have some explanation about how to exploit it at the max.