Survive the Storm / Dust Devils

Dust Devils

Dust Devils are roaming dust twisters. In Survive the Storm every one is a lone, top-strength devil, and what makes a devil dissipate is different from the base game: only domes stop one outright, and everything else it has to wear itself out on.

What makes a Dust Devil dissipate

What ends it	How
A dome	It dissipates the moment it reaches a dome, the same as in the base game.
Wearing out	Once it has knocked 7 hexes' worth of maintenance buildings out of action, it fades.
A Dust Storm	When a Dust Storm begins it clears every active devil from the map.
Its own path	Each devil follows a set path and fades at the end of it, after roughly 8 to 16 hours.

What counts toward wearing it out

As a devil rolls over a building it knocks it out of action (the building malfunctions until a drone repairs it). Only buildings that normally need maintenance count toward the 7 hexes:

Each building is counted once, by how many hexes it occupies - a 3-hex building counts as 3, a 1-hex building as 1.
A building that was already broken when the devil reaches it still counts.
Resource deposits, Dumping Sites and Depots never need maintenance, so a devil passing over them counts for nothing and is not slowed. It keeps going until a dome, a Dust Storm, the end of its path, or 7 hexes of maintenance buildings stop it.

The Dumping Site trick no longer works

In the base game a devil also dies on contact with any large building. Because a Dumping Site is large and builds instantly, a well-known trick is to drop one right on top of a devil to kill it on the spot, then delete the site again. In this mod that does nothing: only domes stop a devil outright, and a Dumping Site (or any other building) never ends one on contact.

What every devil does

Every devil is a Major, Electrostatic twister and travels alone - the smaller sub-devils that used to trail a Major are switched off. As it moves it covers a wide area in dust, knocks the buildings it passes out of action, drains the batteries of nearby drones and rovers and can leave a rover malfunctioning, and hurts any colonist caught out in the open.

How often they come

Dust Devils grow steadily more frequent over the game, from covering 0.1% of the map at escalation sol 1 up to 1% by escalation sol 201. The escalation sol is your campaign day minus your average terraforming, so raising terraforming makes them rarer; the full curve, alongside the other disasters, is on the Disasters page. They do not appear during a Dust Storm: a storm clears any that are active, and none spawn until it passes.

Sources

Part of the Survive the Storm mod. See also Disasters and Escalation to sol 201.