Why your settlers dig up your flags, and which ones they leave alone

Settlers in Dawnsweeper dig up the mines you flag. It can look like a bug the first time: you plant a flag, come back a few minutes later, and the flag is gone, the number beside it has dropped by one, and a settler is walking away with ore.

They do it for room. A flagged mine is ground the village can’t use, and a village ringed by them can’t grow. The note behind it is short: “The point of digging mines is to give them more space to expand.” A settler with nothing more urgent to do takes on a project, and the project’s reason reads like this, from a trace of an Orc trader named Ogrim Ironbelly in one of our test worlds:

takes on a project: it needs doing → a mine at -43,86 holds back the ground → digging up the mine at -43,86

Fifteen seconds later he had dug it up. It was his first dig.

Digging is a skill. A settler who has never done it has a 10% chance of setting the mine off, which we call a bloom: the ground around it re-covers like a burst, flags included. A bloom isn’t your mistake, so it costs no streak and never wakes a Nest. Each dig makes the settler better, and after five digs (two for a Dwarf) they never bloom again.

How the 1.0 rule broke the wall

In 1.0 a settler would dig any flag within 16 cells of a standing building, as long as every cell around the flag was open, flagged or a crater. That last condition was meant to keep a dig from ever opening ground to the Creep.

It wasn’t enough. The flags that hold back the Creep are exactly the flags whose neighbours are all open: you flagged them, revealed everything around them, and the numbers beside them went green. They were the most diggable flags on the board.

Picture a solved square with a ring of open zeros between it and the Creep. The zeros aren’t a wall. A 0 only seals when it has no covered neighbour, so the Creep eats them layer by layer. The square’s edge numbers are the wall, and their flags are what make them sealed. Each dig lowers the numbers beside it. A number that drops to 0 stops sealing as soon as Creep touches it. A few digs, and the Creep walks into the village.

We built that picture as a test: a square walled by 192 flagged mines at radius 24, open zeros at radius 26 between it and ground the Creep takes, and 8 control mines inside, with no blooms allowed, so the only question is whether clean digs breach the wall. Under the 1.0 rule:

• the first wall flag was dug at 1 minute 4 seconds;
• the Creep broke through at 12 minutes;
• 78 of the 192 wall flags were dug;
• the village peaked at 12 people, was down to 6 at one hour, and was gone by an hour and a half.

Nobody made a mistake in that run. The player’s wall was perfect. The settlers took it apart one sensible dig at a time.

The hold line

The rule since 1.1 asks a different question about each flag: could the Tide ever get near it?

The game works out everywhere the Tide could ever reach on the board you can see: covered ground, plus every open cell that isn’t a sealed number and connects to an open edge. A flag more than 4 cells from every standing building is dug only if nothing within 2 cells of it is in that reach. So the flags that make up your frontier, the line the Creep will eventually stop at, stay where you put them.

Close to the village it’s different. A flag within 4 cells of a building is dug under the old rule, because that’s where the room to grow matters most and where a hall or farm is waiting for the cell. And near the village the most skilled free adult does the digging, masters first, even if they’re farther away. That keeps blooms away from people’s houses.

The same test under the new rule: 0 of the 192 wall flags dug, the Creep stopped at the square’s edge for the full three hours, and all 8 control mines inside were dug up for room. The village peaked at 17 people.

What it cost, and what it gained

Settlers dig about half as often now. Across 10 test worlds of 4 hours each with a diligent player, digs fell from 756 to 358. We expected villages to suffer for it. They grew: 14.6 villages per world to 18.4, and 413 people to 488. (That was before a world was limited to eight villages, which came later in 1.3.) The time a village spent with a flag holding back its growth fell from 19 minutes to 6, because settlers now spend their digs on the flags that are actually in the way.

We tuned Dwarves along the way. They had mastered digging at 3 digs. With everyone digging half as often, we moved them to 2, so that Dwarves stay clearly the people who dig.

One cost we kept. In those test runs, about one 4-hour world in 40 had a brand-new hamlet bloom on its first dig, next to its hall, before it had any skilled digger, and the hamlet was lost. We left blooms as they are. That was a deliberate decision: the first digs are a real risk.

If you want a flag left alone, put it on the frontier. If a flag is in the middle of your settled ground, it’s room someone is waiting for.