@Ctrekoz You're right — being able to keep tiles close to a city can indeed make borders expand very quickly, and that could be a balance concern as you mentioned. Separating fortress-claimed tiles from culturally acquired tiles would put a heavy load on memory, so I had to make it so that tiles within 5 tiles of a city are always retained (this was actually the original author’s intention!). Instead of removing this effect, I’ll try adding some logic so the AI can also make better use of fortresses. Thanks a lot for the feedback!

Thanks! I'm still not sure about using this mod due to balance concerns, like too easily getting territory, and idk how AI uses it as well.

@Ctrekoz Hello! Thanks for the question. Here's a quick explanation of "Dynamic Border Retention":

In short: It's a "safety zone" around your cities that protects both the fort tile and its surrounding territory from disappearing. This zone gets bigger as you research new techs.

The Problem it Solves: Normally, if you leave a fort empty for 5 turns, you lose its tile and surrounding territory.

How it Works: This feature stops that from happening. Territory gained from a fort is protected as long as it's inside the safety zone. The zone starts at 5 tiles, grows to 6 with Machinery, and finally to 7 with Railroad.

Example: Territory gained from a fort 6 tiles away from a city is only safe from territory loss after you've researched Machinery. Before that, the safety zone was only 5 tiles, so its territory wouldn't have been protected.

Hope this helps!

I do not understand Dynamic Border Retention.