system
Given the following post, respond as if you're commenting on Reddit:
human
[Invader Zim] Why would the Irken regard it as necessary for an invader to take over a planet before commencing an organic sweep? (At least for relatively primitive planets like Blorch and Earth.)

I guess I can understand why the Irken might send a spy/scout type to a planet in case there are any useful technologies/life forms that the Irken could exploit, and I guess I can understand why they might try to use infiltration and subversion against an advanced planet with planetary shields or artillery that might pose a problem for the Irken Armada, but it seems like as far as actual conquest goes, there's no reason they need invaders to actually take over planets that are primitive enough that they couldn't resist anyway: they could just go straight to an organic sweep with their armada.

So why bother with sending invaders against backwards planets like Blorch or Earth?
gpt
Because it isn't an act of war for them, it is entertainment. The armada could wipe all life off of any planet they want or mind control all of the inhabitants with the flip of a switch, forcing them to mine all of the planets resources before killing themselves but instead they send one trainee with a robot slave, a ship, a command center, and a backpack. Why? Because it is more fun that way, for one invader alone with only what you would give someone for a camping trip to conquer an entire world is a challenge and proof of their worthiness.