From Against the Storm Official Wiki

In the end, the Blight came.

Blightrot Cysts during the Storm


Blightrot %

Blightrot is sometimes described as a tax on Rainwater usage. Blightrot generates Blightrot Cysts and these Cysts generate Corruption with continued Rainwater usage. The more water you use in Rain Engines, the more Blightrot Cysts and Corruption you generate.

You can view your Hearth Corruption percentage on the bottom right of your screen. Clicking on the Blightrot Icon will take you to the Hearth Corruption information page, where you can view how many Blightrot Cysts have generated as well as how much Corruption you can spare until 3 random villagers die. You can also hold the SHIFT key and click on the icon to stop all Engines.

Blight Post, Blightfighters and Purging Fire

A Blight Post
A Blightfighter burning a Blightrot Cyst

On the left is a Blight Post, an essential building used to produce Purging Fire Purging Fire which Blightfighters (villagers assigned to the Blight Post) then use to burn Blightrot Cysts during the Storm Season. Viceroys can also build a Hydrant to store extra Purging Fire near buildings that have grown a lot of Cysts. Purging Fire Purging Fire is made by using Coal Coal , Sea Marrow Sea Marrow, Oil Oil or Wood Wood.

A single Blight Post without upgrades can handle a maximum of approximately 20-25 Blightrot Cysts per Storm Season on Veteran to Prestige 10 Difficulties (this number goes down to around 15 at Prestige 11 and above). Beyond this point, Blight Post upgrades or additional Blight Posts will be needed.

Blight Post Upgrades

Blight Posts can be upgraded up to two times:

LEVEL I (Choose 1)
2 Pack of Building Materials Pack of Building Materials + 4 Pipes Pipes

  • Triple Ignition System: Blightfighters and Blight Automatons in this Blight Post need 5 fewer seconds to burn a Blightrot Cyst.
  • Mobile Sparkcasters: Blightfighters assigned to this Blight Post move 30% faster.
  • Blight Automaton: assigns a Blight Automaton that helps burn Blightrot Cysts to this Blight Post. They can't produce Purging Fire Purging Fire and don't take up worker slots.

LEVEL II (Choose 1)
2 Pack of Building Materials Pack of Building Materials + 6 Pipes Pipes

  • Manned Lookout: the use of water in Rain Engines generates Blightrot Cysts 10% slower for every worker assigned to this Blight Post.
  • Alchemical Forge: +50% Purging Fire Purging Fire double production chance in this Blight Post.
  • Blight Automaton: assigns a Blight Automaton that helps burn Blightrot Cysts to this Blight Post. They can't produce Purging Fire Purging Fire and don't take up worker slots.

The Hydrant

A Hydrant

The exact number of Cysts a Blight Post can handle varies depending on the movement speed of your Blightfighters, and also by Cyst location – the less time your Blightfighters spend walking between the Blight Post and the Cysts, the more Cysts they will be able to burn. A well-placed Hydrant will greatly reduce this travel time, and may be essential if the distance between your Blight Post and the infested buildings is too great.

When assigned to a Blight Post, Harpies Harpies have a +10% chance to double their Purging Fire Purging Fire production, and Lizards Lizards get +5 to their Resolve.

Blightrot Cysts and Removal

During the Storm, Blightfighters can burn Blightrot Cysts with Purging Fire Purging Fire produced in Blight Posts. Each Cyst burned removes 50 Corruption. A Blightfighter will burn a Cyst for approximately 15 seconds before it disappears.

A closed Blightrot Cyst
An open Blightrot Cyst

On the left is a closed Blightrot Cyst, Cysts will remain closed during Drizzle Season and Clearance Season, and they are invulnerable during this time. On the right is an open Blightrot Cyst, Cysts will open during the Storm Season, and they are now vulnerable to Purging Fire Purging Fire. Any Cysts left close immediately as soon as the year ticks over and Drizzle Season starts, even if they were in the process of being burned.


Corruption bar in the Ancient Hearth

Blightrot infects Hearths. The more Blightrot Cysts a Viceroy generates from Rain Engine use or Glade Events, the faster their Hearths get corrupted during Storm Season, when Blightrot Cysts open up. Once the Ancient Hearth reaches the Corruption limit, it triggers Voice of the Sealed Ones. Voice of the Sealed Ones sends out 3 ghosts from the Ancient Hearth that seek out and kill 3 random villagers. As soon as the Hearth discharges, Corruption is reset to 0 and starts rising again.

Lowering Corruption

The only reliable way to lower Corruption during Storm is to employ the help of Blightfighters in a Blight Post. Every Cyst burned lowers Corruption by 50. Once all Cysts have been burned, any new ones will not open up till next Storm Season. Any Cysts left close immediately and Corruption resets to 0 as soon as the year ticks over and Drizzle Season starts.

You could also remove Cysts by destroying all of the buildings that have Cyst slots. Most buildings you construct have them. With only the Main Warehouse left, you will have no more than 6 Blightrot Cyst slots.

Corruption Resistance and Corruption rate

Corruption Resistance or Hearth Resistance is a measure of how high the Corruption limit is. The higher the Corruption Resistance, the more time it will take for Voice of the Sealed Ones to activate. An Ancient Hearth that hasn't been upgraded has 1000 Corruption Resistance. Every Ancient and Small Hearth level raises Corruption Resistance by 150. It can also be raised with different effects.

The Corruption rate per Cyst is 60 Corruption/minute up to Prestige 10, and 90 Corruption/minute from Prestige 11 onwards.

Assuming a Hearth upgraded to level 2, you will reach the Corruption limit of 1300 at least once without burning any Cysts:

  • At 60 Corruption/minute in a 2-minute Storm with 11 Cysts.
  • At 60 Corruption/minute in a 4-minute Storm with 6 Cysts.
  • At 90 Corruption/minute in a 4-minute Storm with 4 Cysts.

Forest Mysteries influencing Corruption

Mystery Penalty Activation
Unyielding Corruption.PNG
Unyielding Corruption
Favoring unavailable if Hearth is Corrupted. Hostility 3
-300 Hearth Resistance. Hostility 2

Difficulty Modifiers influencing Blightrot

Difficulty Modifier Description Explanation
Icon PrestigeMod BlightSwarm.png
Prestige 3
Large swathes of Blightrot migrates accross the realm. Every third Clearance Season, 5* Blightrot Cysts will spawn.
Icon PrestigeMod SinisterBlight.png
Prestige 11
The Blightrot's impact is stronger. Blightrot Cyst generation rate is now increased by 100%, the Hearth Corrupts +50% quicker than normal and all effects that spawn Blightrot now add twice as many Cysts.

*before Prestige 11.

Forest Mysteries and Blightrot

Mystery Penalty Activation
Natural Filtration.png
Natural Filtration
Using Rain Engines causes a lot less Blightrot contamination due to the natural filtration processes of the surrounding vegetation. Blightrot Cysts grow 50% slower when using Rain Engines. Drizzle
Burning Cysts takes 5 seconds longer. Hostility 2
Blight from the Sky.png
Blight from the Sky
Every Storm Season, 1* Blightrot Cysts appear in the settlement (multiplied by the number of years that have passed). Hostility 4
Blightrot Infection.png
Blightrot Infection
When a villager leaves or dies, 2* Blightrot Cysts will appear in the settlement. Hostility 3
Rotten Vapors.png
Rotten Vapors
Pay 5 Drizzle Water Drizzle Water x number of years, or 3* Blightrot Cysts will spawn. Hostility 3
Spreading Contamination.png
Spreading Contamination
+5% faster Queen's Impatience gain for every Blightrot Cyst in your settlement. Hostility 4

*before Prestige 11.

Glade Events and Blightrot

Effect Event Type Explanation
Engine Corrosion.png
Engine Corrosion
Blightrot Cauldron Event Consequence Contaminated liquid gets inside Rain Engines through underground pipes. Using water in Rain Engines generates Blightrot Cysts 50% quicker.
Growth Medium.png
Growth Medium
Rainpunk Cauldron Working Effect The Blightrot inside the Rainpunk Cauldron feeds on everything it encounters. For every 20 food produced, 2* Blightrot Cysts are spawned in the settlement.
Voice of the Forest.png
Voice of the Forest
Withered Tree Working Effect Trees communicate with each other through their roots, making the forest aware of your every move. Spawns 1* Blightrot Cysts every 120 seconds for every 2 Dangerous or Forbidden Glades discovered.
Effective Parasite.pngEffective Parasite Withered Tree Event Consequence The Blightrot feeds on the tree's valuable nutrients, making new Cysts much more resilient. Cysts burn for 5 seconds longer.
Friend or Foe.png
Friend or Foe
Corrupted Caravan Working Effect The forest is merciless to those who exploit it. To protect itself, it may even sometimes ally with the Blightrot. Every 120 seconds, 1* Blightrot Cysts are spawned for each earned Hostility level.
Straight to the Hearth.png
Straight to the Hearth
Corrupted Caravan Event Consequence Your settlement's strongest and weakest point has become a direct target for the Blightrot. Corruption in the Ancient Hearth grows 50% quicker.
Blight Incantation.png
Blight Incantation
Altar of Decay Working Effect A powerful, necrotic curse. Burning Blightrot Cysts takes 10 more seconds. Hostility is increased by 45** points for every Wildfire Essence Wildfire Essence stored in the settlement's Warehouse.
The Nights Embrace.png
The Night's Embrace
Altar of Decay Event Consequence The settlement is slowly engulfed in darkness. Each Blightrot Cyst increases Hostility by 15** points during the Storm.
Awakening Infected Drainage Mole Working Effect Upon awakening the Infected Mole, all dormant Cysts activate and start to Corrupt the Ancient Hearth. Cysts are vulnerable to Purging Fire Purging Fire when this effect is activated. Completing or canceling the Event will not stop the Corruption, and Cysts will remain active until burned.
Infected Drainage Mole Working Effect Blightrot becomes extremely aggressive. 8* Blightrot Cysts will spawn in the settlement. Each Cyst increases Hostility by 30** points.
Noxious Machinery Working Effect The machine is somehow connected with the settlement's underground pipe system. You lose 4 units of a random type of Rainwater every 12 seconds. Every 120 seconds, 2* Blightrot Cysts are spawned in the settlement.
Blightrot Outbreak.pngBlightrot Outbreak Noxious Machinery Event Consequence The explosion of the machine will not only destroy everything within a 10** field radius, but will also cause 5* Blightrot Cysts to spawn in the settlement.

*before Prestige 11.
**value on Viceroy Difficulty and higher.

Perks and Cornerstones influencing Blightrot

Blightrot Perks and Cornerstones
Name Rarity Description Sources
Alt Cor Ord Rel
Baptism of Fire Baptism of Fire Legendary Every 3 burnt Blightrot Cysts lowers Hostility by 10. While the Hearth is corrupted, you’re unable to sacrifice resources. x Cor x x
Blight Filter Blight Filter Legendary A crystalline filter designed to mitigate the negative environmental impact of infused rainwater. Blightrot Cysts appear 50% slower when using rain engines, but Reputation from Resolve is generated 90% slower for the next 2 Reputation Points. x Cor x x
Blightrot Pruner Blightrot Pruner Legendary Blightrot spores aren't technically eggs, but they taste the same. You gain 5 Eggs Eggs when a Blightrot Cyst appears in your settlement. x Cor x x
Burnt to a Crisp Burnt to a Crisp Legendary Gain 20 Coal Coal for every 3 burned Blightrot Cysts. x Cor x Rel
Overexploitation Overexploitation Legendary Global gathering speed is increased by 30%, and newly discovered resource nodes have more charges (+10 charges to small deposits, +25 charges to large deposits). Every depleted resource node spawns a Blightrot Cyst. x Cor x x
Corruption Perks and Cornerstones
Name Rarity Description Sources
Alt Cor Ord
Alarm Bells Alarm Bells Legendary The Brass Order's newest invention. All workers have a +5% higher chance of producing double yields for every 90 points of expected Corruption per minute in the Ancient Hearth. x Cor x
Alarm Bells (Stormforged) Alarm Bells (Stormforged) Mythic The Brass Order's newest invention. All workers have a +33% higher chance of producing double yields for every 100% points of expected Corruption per minute in the Ancient Hearth. Alt x x
Ancient Stabilizer Ancient Stabilizer None The Ancient Hearth's resistance to corruption is increased by 100. x x Ord
Firekeeper's Armor Firekeeper's Armor Epic Allows firekeepers to combat corruption more efficiently. Every burned cyst removes an additional 50 corruption. x Cor x
Forbidden Seal Shard (Stormforged) Forbidden Seal Shard (Stormforged) Mythic It was not you who removed this fragment, weakening the ancient seal - but you would still be executed on the spot if someone was to find it in your possession. Every Glade Event solved by making a decision marked as Corruption increases the chance of workers producing double yields by +5%. (the bonus is added retroactively) Alt x x
From the Shadows From the Shadows Legendary Confused, empty-eyed creatures emerge from the Hearth. Each time Voice of the Sealed Ones triggers after the Hearth reaches 100% Corruption, 3 new villagers appear in the settlement. x Cor x
Obsidian Runestone Obsidian Runestone Epic A complicated runic structure, designed to shield the hearth from corruption. The Ancient Hearth's resistance to corruption is increased by 400. x Cor x

Plagues and Blightrot

Plague Description Explanation
Plague of Corrupted Water.png
Plague of Corrupted Water
The Rainwater has become contaminated, so Rainpunk machinery is now even more hazardous. Using Rainwater in Rain Engines generates Blightrot Cysts 100% quicker.


You can generate Blightrot Cysts even without goods production by leaving workers assigned and the secondary resolve-boosting engines turned on.


Thanks to Discord users Jhazrun, Aphant and Benedict for supplying much needed information to complete this page!