Hello! This is my idea for a new event in Starbound!~ I want to see "Planet Raids". Pretty similar, yet different, like invasions in Terraria. Maybe they can be story-related too! For example, if your colony has 5+ apex rebels, Miniknog soldiers can raid your planet! You will have to fight back, ofc. Here's another one: Asra Nox's cultists can sometimes go to your planet. If you are unlucky enough for them to find your colony, you will have to fight back too! If they wont find your colony, they can just leave something behind, like a small camp or something.
It could use more detail...And I already made a suggestion about it which is more detailed, since the suggestion wasn't anything new. As for your suggestion, literally all you're suggesting is that hostile NPCs sometimes spawn in groups.
It kind of already had mechanics for spawning enemies and making them spawn structures. What you should do is to instead take a more original approach, or use different mechanics. After all, while we got the same idea, it was in a different way, so make it the way you want it to be, even if it overlaps (Which, considering the broad subject it actually is, means that it would be inevitable).