system
Given the following post, respond as if you're commenting on Reddit:
human
[Dune] So the Sardaukar are the Emperor's personal forces, and each house has it's own private guards/militia. But is there like an actual army that belongs to the Empire itself?

Is there an army that doesn't directly belong to the Emperor or any of the houses? Maybe used to conquer new planets and fight hostile alien life they find on them?
gpt
No, it’s just the Emperor’s Sardukar. There is no central force of the Imperium besides that of House Corrino, so who would they answer to?

Anyway, there isn’t any sort of alien forces to defeat. There are no intelligent aliens anywhere in the Dune universe. So who would this hypothetical army fight? And on whose behalf?