Will Fallen Empires attack me if I build a starbase in a neighbouring system to them?

[EAST]

Will all types of Fallen Empires attack me? Or just specific ones like The Holy Guardians? Back when I only had the base game some years ago I got attacked by one of them when colonizing a planet in one of their neighboring systems. Is it still the same? I have all the DLCs.

[Elitewrecker PT]

Only the Militant Isolationists attack you for claiming a neighbouring system. Holy Guardians only attack you if you colonize a Holy Planet.

[Renzokuken]

Isolationists will attack you for colonizing a system that borders them, it's good to note that bordering an empire means owning a system where the next hyperlane jump is connected to their space. Just because your borders touch, doesn't mean you're necessarily close enough for them to attack you.

Holy Guardians will attack you if you colonize one of their Holy Worlds, if you see a fallen empire and you see gaia worlds near them check for the holy world modifier, if you see that steer clear or they'll rain holy fire on your a$$.

[Elitewrecker PT]

You can claim the systems, you just can't set foot on the planets.

[_ALuX_]

Militant Isolationists will do that. It gets even worse when they become Jignostic Reclaimers later.

[EAST]

Cool! Thanks!