How to Prevent Infestations

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Bug hives aren’t just an annoyance. They will slowly spawn bugs and produce additional hives becoming a full scale infestation. These little creatures can be devastating. Even if you manage to get rid of them, there is a good chance that half your colony will get wrecked in the process. Unfortunately, if you build underground there is no way to stop infestations from happening. But here is some knowledge that will help you take steps to control infestations and ensure the minimum damage.

Where and when do infestations happen

Infestation events can’t be predicted. They happen in the same way that raids and sieges do: whenever the AI storyteller decides it’s time for one. But you can predict WHERE will they spawn. Here’s how to game decides where in your base to spawn an infestation.

For an area to be suitable for an infestation, it has to be:

  1. Under a mountain roof.
  2. On an unblocked area.
  3. On a place not too cold.
  4. Inside a connected area of, at least, 16 tiles.

Ways to prevent infestations

Give homeless bugs a “place to live”

When the AI spawns hives, it calculates per square. This means that if 50 squares in your colony are overhead mountain and you have 150 squares of mined area outside of the base, the AI will throw 10 hives, and only 3 hives will spawn in your base.

Sweet Cold Death

Hives won’t be spawned in places where the temperature reaches -17 ºC or lower. But beware, if you have a 300 squares mined area and only the sleeping quarter is above -15 ºC, the AI will shove all of the hives into that area. In addition, turning your base into a permanent fridge wastes a large amount of power, and requires the use of parkas.

Don’t build underground

The only definitive way to prevent infestations is to not build anything you care about in the mountains. You can avoid building essential facilities such as bedrooms and dining rooms inside the mountain. While that is a viable solution to prevent bug infestations, underground bases have a lot of benefits compared to outside bases despite the hives.

How to deal with the bugs

Bugs posses high armor and a high DPS due to a fast attack speed, which also serves to stagger-lock your colonist. They also move somewhat fast, meaning that your colonists will never escape melee with them. Bugs are also very durable. They posses 15% armor and several redundant hit locations that rarely reduce the bugs’ effectiveness.

Bugs are difficult to effectively plan against. While the spawn algorithm favors dark rooms and rooms further away from the “center” of your colony (Debug, View settings, Draw infestation chance), they can effectively spawn anywhere underground. A bug trap spawning ring encircling your base is a good way to control where the infestation does spawn, but this costs both time and space. It also requires a great deal of pre-planning and makes it incredibly difficult to build a “natural” colony.

Freezing or burning the bugs can kill them without the loss of too many colonists. Freezing works but due to the large power and component cost it is not very practical. Burning is cheaper, only requiring wood, but will often destroy much of your colony in the process. In ether case, these methods take time and will not help the colonists nearby the infection. This is, at best, a way to mitigate further damage once the infestation has already begun.

In any case, never let the bugs grow and multiply or it might be too late. If you can’t beat the bugs before second reproduction, you might not ever be able to beat them.

Infestations to the test

Check out this video by Bjorn Strongndarm in which he explains and tests all mechanics referring to infestations in Alpha 17, such as where are infestations more likely to happen and how to deal with them: