Short version, with all the buffs advent loyalists get to their culture rate, their culture easily goes to unstoppable and wipes all the planets at their borders. Is there some countermeasure to this, as at the moment there just seems to be nothing I can do?

Long version, I was playing a game with 9 AIs. At some point one AI (Advent Loyalist) either got some research done or built alot of temple of communion. Whatever it did, it took almost 50% of the galaxy culture in a really short time, destroying colonization of more than 10 enemy planets with this. To this point that AI wasn't really far expanded but it managed to even purge colonization on planets which weren't even border worlds, but 1 behind, so strong was the culture of them.

After that I tried to play like this myself as Loyalist (played Rebel before) and it's just ridiculously easy to go and roll over enemies, if you just go and put some temples there and wait for enemy planets to die. Even capital ships won't help much there, as you would need more capitals to protect your planets, than you can actually have if there are like 5 or more planets in danger to be purged by culture. Also, as long as you defend your planets against the culture with them, you can't go and attack with them.

The most extreme thing was taking a desert planet and building only temple of communions there. The culture was going berzerk with any close enemy planets there. Even purging planets 2 phase lanes away.

I think building the loyalist on their culture is a really nice idea, but at the moment, it seems too strong to me. Advent rebels need to be in their culture for alot of their bonus, TEC loyalist need to be at their planet (which will be purged by culture and then Advent loyalist can clean up the defenses, even TEC loyalist might lose to Advent Loyalist in Advent culture and without their militia boost from planets).

It might of course differ against human players, but AI was really really susceptible to this, and with my Advent Rebel I was also wondering what I could effectively do against it.

Just wanted to point this out, maybe other people don't see this as troubling?