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.

Cold snap

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

When a cold snap starts, immediately harvest any viable crops exposed to the outside. Once a crop reaches 65% maturity you can partially salvage produce from them, while if they 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.


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. Since many also eat meals or produce, you will need to take this into account when stocking up food.

Keeping warm

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 geothermal generators which provides constant power 24/7. 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

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.

Firefoam poppers

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.

Heat wave

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

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 research 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 obviously increase power expenditure.

Psychic drone

This event causes the mood of most colonists of a selected sex to drop by a large amount (-15, but dependent on traits) 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.

Humanoids are the only ones affected in this event.

Trait effects

Some traits affect the sensitivity a colonist is to psychic events.

  • Psychically sensitive and hypersensitive colonists will suffer greatly during this event as their increased sensitivity corresponds to a greater mood drop.
  • On the contrary, psychically dull colonists are less affected, and psychically deaf colonists won't feel a thing at all.

Countering the mood drop

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 joy hours and spread them throughout the day so they will constantly have a +5 to +10 mood buff from joy.
  • Allow your colonists to have some social drugs to lift their spirits. Don't give too much otherwise they risk addiction.

Psychic foil helmets

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.

Solar flare

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 early-mid to late-game 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 quickly die. Manually harvest them before they wither completely.

Plants growing in a sheltered greenhouse with a sun lamp but not hydroponics won't grow during the power outage. If your colony is reliant on heaters and the temperature dips low enough they may die, but this can be prevented camp fires.

Fueled alternatives

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, as opposed to heat waves in which a well-built freezer may still be able to retain sub-zero temperatures.

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

Temperature control

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.

Toxic fallout

A persistent event that poisons the atmosphere with toxic dust, slowly sickening animals and humans, 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.

Staying indoors

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.


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

Fallout retreat colony

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.

Volcanic winter

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.


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 lighted greenhouses can help with crop growth during volcanic winters.

Poison Ship

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


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.