Not every galactic ruler will have an easy time controlling the galaxy in Stellaris. Eventually, several empires will attempt to take a stand against those who have taken control of everything. You have the option to oppose the Galactic Imperium. Still, if you want to work towards sparking a rebellion, you’ll need to launch multiple espionage missions against the Imperium, and it also means working alongside allies to prepare for the upcoming war.
How to spark a rebellion
If you wish to uprise against the galaxy’s Imperium, you’ll need to start espionage missions against them. You’ll need to devote an envoy to the operation, and they will have to create a spy network against that empire. It’ll be a similar process to any other espionage mission you can take against the other empires in Stellaris. You’ll have additional operations against the Imperium, such as weakening their authority and having the choice of sparking a rebellion.
The Spark Rebellion option is the more difficult task to pick. We highly recommend you do this after you’ve obtained additional intel against the Imperium, and you have plenty of assets at your disposal. The Spark Rebellion operation works similarly to the other espionage choices. However, once it finishes, the big difference is that you’ll have created a galactic rebellion federation that will be united in defying the Imperium.
You can expect to go to war against many of the more powerful empires, especially those who favor the Imperium in power. The best time to choose the Spark Rebellion operation is when you’re ready to go to war. You’ll want to have plenty of empires who consider you an ally and several warship reserves. You’ll be battling against one of the superior powers in your galaxy, and they won’t go easy against you.