# How does village border growth work in Reus?

What are the factors that control when and how the border posts move?

I've read a couple of theories, and made some observations, but it's still pretty unclear to me. I saw a number of ideas floating around on the internet, and did some pseudo-exact experiments of my own; I'll put some of those up as food for discussion later.

The first I did experiment was digging an ocean, planting a forest, putting down a fruit tree and then waiting. After the settlement, I marked the borders by putting down a Reus and then regularly checking to see if they'd expanded. They did, with an interval somewhere between 3 and 4 minutes, with no apparent bias to left versus right. This was on a 30-minute world.

Anecdotal evidence, because I still have to try the following varying factors:

• Longer world. I feel the rate should slow down for 120-minute worlds, but I haven't tried that yet.
• Neighbouring biomes: does it take longer to go into the ocean, say?
• Local availabilty of prosperity: does a village with two food grow faster or slower than a village with 80 excess food? That could be tested with some extra elder/strawberry combos.
• Total availabilty of prosperity: does it make a difference if a village half the world over has way too many resources?
• If it's slower in a 120 minute world, it's not by a lot; I keep moving to focus on another village only to find that by the time I check on the first one, it's doubled in size. – Yamikuronue Aug 25 '13 at 19:54
• @Yamikuronue You're right, it doesn't matter. I should update my answer here with the information I found out in forums.abbeygames.com/viewtopic.php?f=3&t=781 (and I should update that answer to 1.1.2!) – yatima2975 Aug 26 '13 at 7:05
• Yesterday I had a situation where I had a village with a lot of danger not grow for quite some time -- something like 20 minutes. I had been ignoring them, so it might be that they capped out their prosperity, or the danger might have mitigated it, but neither factor is mentioned in this answer – Yamikuronue Oct 23 '13 at 12:17
• Neighbouring biomes: does it take longer to go into the ocean, say? I saw a post somewhere by one of the guys who worked on the game saying that it does expand slower into oceans, though he didn't mention any of the other biomes – Skytiger May 4 '14 at 7:58

A village has so-called 'reach points', these get increased every 5 seconds by 0.025 points (so a full point every 200 seconds). Also every 5 seconds, a village checks to see whether it can expand its borders. Each new tile has a buy cost, and if a village has enough reach points, it gets the tile (with a slight preference for expanding to the left - but I'm sure which that direction that actually is!). If it can't afford either tile, it just keeps accumulating reach points, so that when a bottled up village has one of it's neighbours destroyed, it can expand quickly.

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