Events Guide

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This guide is about surviving natural events that the game throws at you. To defend your base against offensive threats, see Defense tactics.


A successful colony should be able to stand up against most events without problem. This includes several aspects.


Cold temperatures can kill plants. This is a more concerning issue for colonies continuing to grow crops in the winter, when temperatures can wipe out entire harvests.

Heat, on the other hand, can't kill plants, but can stifle their growth greatly.

Light levels are another major factor in plant growth. It can't grow in places with light level below 50%, and some events affect external light levels.

While crops grow rapidly in hydroponics basins, they have a drawback: if they are disconnected from power, the plants inside quickly die. Some hard power-outages, such as solar flares, are damaging to colonies relying on these. Other events may also end in power outages that have the same effect, if precautions are not taken.


Always keep a great stock of food at hand in case of hard times. Stock up at least 20 days of food, with more the shorter the growing season, so you can survive the winter or extended events such as volcanic winters.

While stocking on food, consider the animals as well, as outdoors plants may be rendered inedible, or it's not safe to go outside for food.


While solar power seems reliable at first, regularly and predictably powering the colony, it should not be relied on as the sole source of power as the light level is affected by many events, like the Eclipse, therefore affecting the power available to the colony.

To fix this, add some wind turbines into the mix, which isn't affected by light level, though its power output is somewhat unpredictable. Once researched, geothermal generators are a must-have, as they provide large amounts of power 24/7.

Batteries are essential for any colony that uses solar or wind power. Make sure you give the ability to disconnect groups of batteries from the grid, so in case of a short circuit less power is wasted and less damage is done.


One of your crop fields has contracted a plant disease. If it is too close to another field, the infection may have spread to even more plants before your colonists detected it. Plants struck by blight show a clump of yellowish blotches and will die within a day or so. These plants must be cut very quickly, or the blight will spread even further.

Attempting to harvest blighted plants that are 100% grown will yield nothing.

Cutting all affected plants gets rid of the blight. If it is not dealt with, it will spread to any nearby crop field and destroy any crops.

There is no way to stop blight from occurring. You can minimize the damage it can do by how you set up your growing zones. A gap of 4 tiles with no plant coverage prevents the spread of blight. Blight will only strike one field at a time, as long as they are sufficiently separated. So it is a good idea to have more than one growing zone for very important crops, and to make sure no individual growing zone is so large that its loss would be a catastrophe.

Wild plants are never affected by blight.

Cold snap[edit]

A cold snap sends temperatures plummeting, reducing temperatures by 20 °C for several days.

The main threat of cold snaps is hypothermia, which strikes early-game bases much harder. Crop death is also an issue, and can disrupt many bases that lack greenhouses, or grow crops outdoors throughout the winter and thus don't stock up food to prepare for it.

Crops and plants[edit]

When a cold snap starts, immediately harvest any viable crops exposed to the outside. Crops begin to die at -10C/14F. If a crop has reached 65% maturity you can get some produce from harvesting it; if the plants die it will be lost.

Crops growing in a warmed greenhouse won't be affected, so you may build some to negate the effects of cold snaps in crop growth. If your crop fields are already walled, you can put roofs over them and add heaters or campfires to keep them from dying. They won't grow without daylight or a sun lamp. But a cold snap should not last long enough to cause them to "die from rotting" due to lack of light.


When all your crops are culled by the cold, you will need some time before you can harvest from your next batch of crops. Thus, keep a plentiful food storage on hand.

Grazing animals may also starve as the grasses shrivel up, rendering them inedible. To combat this, keep haygrass or kibble handy, and forbid them, only allowing animals to eat them when crises arise.

Any animal except wargs can eat simple meals. So you can feed simple meals to grazing animals even if you have only meat available.

Keeping warm[edit]

To keep your colonists warm and protect them from the cold, make jackets, dusters, tuques or in harsher conditions parkas, and give them to colonists that do a lot of outdoor work (excluding growing, which is impossible in the cold weather). If you don't have enough fabric or technology to make better clothing, keep the rest of your colonists indoors, which you can warm up.

While you can rotate your workers to allow recovery from the cold, it's not recommended to do so due to frostbite.

In early-game, you can chop down trees to make campfires for warmth. Later on, build enough heaters in each room to keep them warm even in cold snaps.


A short-lasting event that causes the outdoor brightness to greatly lower over its duration.

Overall, this event does not cause much harm on its own, however when combined with other events it can complicate matters.


It has a great impact on colonies reliant on solar panels, which will barely function during an eclipse.

To counter this, build wind turbines which continue to produce power without light, and wood-fired generators, chemfuel powered generators, and geothermal generators, which provide constant power. These help to fill out part of the energy deficit caused by your solar panels not functioning.

Building additional batteries to help collect power when sunlight is plenty may ease the situation a little.


During an eclipse outdoors plants won't grow due to the low light levels. This doesn't really have an impact on already well-stocked bases, but you're critically low on food and really need that harvest to come, it can spell doom.


During flashstorms, lightning rapidly strikes a small area, setting it on fire. In plant-rich areas, the fire can spread across the map, potentially causing great damage. It also delays the presence of rain, giving time for the fire to spread before being put out.

Active extinguishing[edit]

If you have spare colonists on hand, you can direct them to preemptively extinguish the fires before they spread out of control.

Draw a home area over the area affected by the flashstorm, and colonists will automatically go and put out the fires. If they are fast enough, the 3x3 squares of fire left behind by the lightning will be contained without much spreading. Be sure to remove home area afterwards, or else you may find your janitors out in the hinterlands cleaning dirt.

Firefoam poppers[edit]

You can relocate some firefoam poppers, either to somewhere in your base facing the advancing fires as a defense, or to directly extinguish fires and preventing them from spreading to the foam.

Keep in mind that firefoam poppers are rather costly and one-use.


In biomes with heavy plant growth such as tropical swamps, sending colonists to extinguish fires is often an exercise in futility. It is therefore necessary to prevent the fire from getting too close to your base in the first place.

A 4-tile-wide gap prevents the spread of fire. A stone or concrete floor is a great way to do this if the ground can support it. Another method is to put up a stone wall, or even single segments of stone wall, and build a roof from them out to a distance of 4 tiles. Once a patch of ground has been roofed over, no more plants will grow. It's possible to do this using a stockpile of stone chunks or by regularly sending plant cutters to clear the ground manually, but those methods are more labor-intensive and less effective.

Heat wave[edit]

The opposite to a cold snap, this causes temperatures to rise by up to 17 °C for a few days.

The main danger arises from freezer failure, which can cause food to start spoiling in an inadequately cooled freezer that can't beat the heat. It can also cause heatstroke which greatly affects outdoor workers.

Since plants don't usually die except in the hottest of regions, this event is usually less damaging than cold snaps economically. However, extreme heat is less comfortable than extreme cold, and is slightly harder to beat.

Keeping cool[edit]

To keep your colonists cool and protect them from the heat, make cowboy hats, bowler hats and dusters. These three pieces of garments are the only ones that provide heat insulation.
If you don't have the technology to make these then you should rotate your outdoor workers in shifts so they have time to recover between exposure to heat.

Make sure you have enough coolers to keep cool even in the middle of a heat wave. In tribal starts it may be worth it to build passive coolers in order to cool down rooms before you have electricity.


Double walling freezers helps with insulation against heat, helping your freezer stay functioning in heat waves. Make sure you don't block off the exhaust port of the coolers otherwise they won't function.

The more straightforward solution to this is to build even more coolers, though this will require more power. A way to do so a bit more efficiently is to have two coolers set to different temperatures. One cooler set to a moderately cold temperature, for example, -10C, will be on low power mode most of the time and only kick in when the outside temperature is very high. A second cooler set to a very low temperature, for example, -30C, will be on high power mode all the time.

You can also temporarily forbid the door to your freezer to slow the loss of cold air during a heat wave.

Psychic drone[edit]

This event causes the mood of most colonists of a selected sex to drop by a large amount (-15, but dependent on psychic sensitivity) over a few days. While a -15 mood isn't too harmful if your colonists are well cared for, it can add insult to injury if you are already suffering from other additional events or are trying to rebuild in their aftermath. High psychic sensitivities can make the penalty totally untenable while low sensitivities might make it negligible or even non-existent.

Humanoids are the only ones affected in this event.

Countering the mood drop[edit]

You can do the following things to alleviate the mood drop. The drone lasts only a short while so temporary measures are okay.

  • Give colonists more recreation hours and spread them throughout the day so they will constantly have a +5 to +10 mood buff from fulfilling their recreation needs.
  • Allow your colonists to have some social drugs to lift their spirits. Don't give too much otherwise they risk addiction.
  • If a pawn's negative thoughts can't be countered - for example, a neurotic colonist whose spouse recently died - you can anesthetize them for a day. It won't make them feel better, but it's impossible to have a mental break if they are unconscious.

Psychic foil helmets[edit]

A niche item that comes into good use here. It's best to equip these on those most affected by the psychic drone, or those already suffering from a low mood due to other things. However, it is terrible for blocking damage, so remember to switch back to regular helmets if needed.

It can be effective to forbid psychic foil helmets in your colonists' everyday Outfit in the Assign tab. Prioritize a high risk colonist to force-wear the foil helmet during the psychic drone. Then when the drone is over, go back to the Assign tab and clear the force. They will automatically remove the helmet and choose more appropriate headgear.

Solar flare[edit]

A highly disruptive event that shuts down all electrical devices with electromagnetic pulses. Its disruptive potential is magnified should another event coincide with it, such as heat waves, and the fact that it cannot be countered (i.e. no ways to prevent shutdown of electronics in the basegame) does not help either. Devices not using power are immune.

It chiefly affects all colonies that have electric appliances in them. Colonies extensively reliant on electricity, such as those using hydroponics farming or turrets, are especially affected.


Plants in a shut down hydroponics system will die over time in case of power cut, but time required for them to die exceeds the time of solar flare, so this is not a problem you should worry about. More dangerous problem for plants is cold, from which they die almost instantly. To avoid this, in advance put a campfire (prohibit refueling) with a stack of wood stored near it in hydroponic room. When flare appear, manually order any pawn to fill a campfire. It has been tested in practice that one campfire is enough for a room of 20 hydroponic farms at -40 outside. Plants growing in a sheltered greenhouse with a sun lamp but not hydroponics just won't grow during the power outage, but still can die from cold.

Fueled alternatives[edit]

Some production buildings have a fueled variant that consumes wood instead of power, and are immune to solar flares. This allows for production to continue during solar flares.

For lighting, torch lamps also work, though they emit a softer light.

However, these all take up additional space, so they may not be worth building. If you are encountering additional power issues then they may be worth a try.


Another structure hit hard with flares, freezers will stop functioning completely (nothing can be done), as opposed to heat waves in which a well-built freezer may still be able to retain sub-zero temperatures. While the maximum duration of the solar flare is not long enough to cause meat to rot, it can significantly impact the remaining rot time of the stored food, rot food that has not been immediately frozen after collection, and if the freezer cannot be brought down to temperature rapidly enough, rot can still occur after the solar flare has finished.

Double-walling freezers help keep in the cold for slightly longer.

Temperature control[edit]

If temperatures are outside comfortable range, you can remedy this using the more traditional campfires or passive coolers. However, since solar flares don't last too long, this may be worth the effort only if colonists are at serious risk of hypothermia or heatstroke.

Turrets and mechanoids[edit]

Colonies that rely on turrets and mechanoids for their main combat power are most vulnerable to solar flares in the event of a raid. Turrets will not fire, while combat mechanoids may go out of control due to lack of throughput due to the Band node being disabled. Although the duration of the solar flare is not enough for them to go wild and become hostile, while it is going on the mechanoids will wander aimlessly around the settlement without the possibility of control. If the remaining bandwidth allows, you can disconnect from non-combat mechanoids to free up space for combat ones.

Toxic fallout[edit]

A persistent event that poisons the atmosphere with toxic dust, slowly sickening animals and humans - inflicting toxic buildup, killing plants, as well as slightly reducing brightness outside.

This is a highly dangerous event across all stages of the game, severely punishing outdoor activity and killing crops.

Stay indoors[edit]

Unless necessary, you should have everyone (including animals) stay underneath a roof so they won't be affected by the toxic fallout. For those that do need to get out, make sure to limit their exposure and give them plenty of time to recover.

Hunt quickly[edit]

For approximately the first day of toxic fallout, wildlife can still be hunted and butchered. When the animals' toxic buildup gets too high, they will instantly rot upon death. After the first few days any surviving wildlife will flee the map entirely. Get all the meat you can while it's still possible to do so. Note that boomrats and boomalopes will not flee the map and can be hunted later, as they are not affected by toxic fallout.

Plan ahead[edit]

Set up a "roofed" allowed area before this event occurs. A roof extending one or two tiles around the edge of your base, and roofed walkways supported by pillars leading out to your crop fields or perimeter wall, will be a lifesaver. Any pawn whose toxic buildup goes from "initial" to "moderate" should be restricted to the roofed zone.

If possible, have a dirt-floor greenhouse set up and ready to go. You can build a sunlamp in the middle of a sunlamp-shaped crop field and make sure it is turned off until you need to build a roof over it and turn it on. You could also build a backup sunlamp, uninstall it and keep it in storage. This will allow you to quickly build a roof and power up a sunlamp over an existing crop field as soon as toxic fallout arrives.

Although it's best to surround a greenhouse with walls for protection from raiders, it's not strictly necessary. Even if you've just moved your colony to a brand new tile and get a long toxic fallout immediately upon arrival, you can throw down a couple roof support pillars, a sunlamp and a growing zone and start planting.


You can still continue to grow crops outdoors, but less successfully. To maximize the chances of successful harvest, grow fast-growing crops such as rice and harvest them quickly.

For a tribal colony that has not yet researched electricity, this may be the only option. However, most tribes will be able to research electricity within the first two or three years; toxic fallouts should not last more than a quadrum or so during that time.

Fallout retreat colony[edit]

Just make a quick caravan and move your people to another world map tile, preferably with one space between your original position and the new one. This allows you to completely avoid the effects of toxic fallout. However, this also exposes your base to attack as there will be nobody left to defend. This requires raising the colony limit to 2 in the main game options menu.

Volcanic winter[edit]

A long-lasting event where volcanic ash obscures the sun, slowly causing daylight level to drop to 86% of normal values. Because of this, plants will grow slower, solar panels will not generate as much electricity and temperatures will drop.


In an extreme desert, rain is rare and soil is scarce. In other biomes, you should roof your emergency sun lamps.

Volcanic winters won't kill plants outright, but it still has the potential to kill plants should the temperatures drop. You may want to expand your growing zones so you can keep up food production.

Like cold snaps, building warmed and lit greenhouses can help with crop growth during volcanic winters.

Poison Ship[edit]

Poison Ships spread a plant-killing, toxic snow that will eventually cover the entire map. This can devastate outdoor crops, even those in outdoor hydroponics basins, destroying the colony's food supply.


The toxic snow created by a poison ship affects all outdoor plants, in a similar way to the Toxic Fallout event. However, indoor, roofed crops are unaffected, so the tactics for surviving the Toxic Fallout event can be successfully applied here. Interestingly, walls tend to block the spread of the toxic snow. Therefore, surrounding the poison ship with either a roofed or unroofed stockade so that the ship is "indoors" can contain the toxins indefinitely until you are ready to deal with it.

Like the Psychic Ship event, the Poison Ship will spawn mechanoids as soon as it takes any form of damage. Placing an IED so that the ship is within the device's blast radius will also cause the mechanoids to spawn. One tactic for dealing with these threats is to surround the ship with IEDs at a distance of 5 blocks - just outside the blast zone. Then, use a long-range sniper to attack the ship and lure the mechanoids out into the traps.

Legacy events[edit]


For those still playing Beta 18, a tornado can occasionally cut a path of destruction across the map, damaging everything in its way.

It is capable of wreaking havoc on even well-prepared bases, making it dangerous to face across all stages of the game. However, mountain bases are spared the wrath of the tornado as it can't get through the layers of overhead mountain.

Obviously you need to get your colonists out of the way of the tornado. It is easily outpaced by healthy colonists. Incapacitated colonists lying in bed should be moved elsewhere before they are stricken.