Evil biomes

An **evil biome** is a naturally spreading, hazardous biome that has generally negative effects on entities inside or around it. The two evil biomes are The Corruption and The Crimson, only one of which will always spawn in a world. Upon world creation, there is a ~~50\*~~1/2 (50%) chance for either one to generate. On the PC version, Console version, Mobile version, and tModLoader version, a player can choose whether they want Corruption or Crimson to generate in their world or they can leave it to be determined randomly. On the tModLoader 1.3-Legacy version, the player only has this choice if Hardmode has been entered in at least one world.

Corruption or Crimson is saved as the world's naturally generated evil biome, and determines:

* whether Shadow Orbs or Crimson Hearts are generated;
* whether Demon Altars or Crimson Altars are generated;
* whether a Corruption Chest or Crimson Chest is generated in the Dungeon;
* whether Underground Corruption or Underground Crimson is created when the Wall of Flesh is defeated;
* whether some NPCs will sell Corruption- or Crimson-related items during a Blood Moon or Solar Eclipse; and
* which Biome Mimic is spawned when a Key of Night is placed in a chest.

It is possible to create an artificial Corruption/Crimson, seeding an area with the opposite evil biome. While this is traditionally done with materials brought over from another world, there is another option on the PC version, Console version, Mobile version, and tModLoader version: If the Dryad is housed in a Graveyard during Hardmode, she will sell grass seeds from the other evil biome's. This allows, for instance, obtaining the Biome Key  / Biome Key Mold of the opposite evil biome, as that is dependent on the biome the enemy is killed in, regardless of whether it is a "natural" biome or "artificial" biome. This will not however provide a Dungeon chest to go with the key.

The evil biome is predominately comprised of chasms made from infected stone (Ebonstone or Crimstone). However, the biome can overlap other biomes, providing corrupted versions of the Forest, Desert, Snow, Jungle, or Ocean biomes. This can be evidenced by the presence of purple/red grass and Ebonwood/Shadewood trees, purple/red Cacti and Ebonsand/Crimsand, Purple Ice/Red Ice, or purple/red Palm Trees. Infected Jungle areas remain muddy, with the grass simply becoming corrupt or crimson mud grass.

While in pre-Hardmode, the only biome capable of spreading the evil biomes is infected surface Forest, via infected grassy blocks (see below for details).

## Corruption and Crimson counterparts

Certain items are exclusive to either The Corruption or to The Crimson.

The following items are considered counterparts to each other. It should be noted that counterparts do not necessarily share the same stats or behaviors.

## The Corruption

The Corruption presents a purple "corrupted" theme, with purple grass, trees and stone. Thorny Bushes and unique enemies (beginning with Eaters of Souls and Devourers) make the area dangerous and potentially deadly for newer players. The Eater of Worlds can only be summoned in the corruption. The Corruption contains deep vertical chasms (which can easily result in death from fall damage), with cross tunnels well below ground. Shadow Orbs appear deep underground, usually at or near the bottom of chasms. Destroying a world's first Shadow Orb will always drop a Musket and some Musket Balls, which automatically fulfills the criteria for the Arms Dealer to arrive. Destroying three Shadow Orbs will result in the spawning of the Eater of Worlds.

### Corruption contents

Characters
* ​Eater of Souls
* ​Corrupt Goldfish
* ​Devourer
* ​Eater of Worlds(boss)

Hardmode:
* ​Corruptor
* ​Corrupt Slime
* ​Slimeling(from Corrupt Slime)
* ​Shadow Slime
* ​Slimer
* ​World Feeder

Corrupted Desert:
* ​Dark Mummy
* ​Shadow Mummy

Unique TreasuresFrom Shadow Orbs:
* ​Musket(Drops 100 Musket Balls)
* ​Musket Ball(Dropped with Musket)
* ​Ball O' Hurt
* ​Vilethorn
* ​Band of Starpower
* ​Shadow Orb (item)

Unique DropsFrom Eaters of Souls:
* ​Ancient Shadow armor
* ​Burger

From Devourers:
* ​Worm Tooth

From Eaters of Souls and Devourers:
* ​Tentacle Spike

From Eaters of Souls, Devourers, and Corruptors:
* ​Rotten Chunk

From Eaters of Souls, Devourers, Corruptors, Corrupt Slimes, Slimers and World Feeders:
* ​Monster Meat

From Eater of Worlds:
* ​Demonite Ore
* ​Shadow Scale
* ​Eater's Bone
* ​Eater of Worlds Mask
* ​Eater of Worlds Trophy
* ​Treasure Bag(Drops the Worm Scarf in Expert Mode)
* ​Writhing Remains(Dropped rarely in Master Mode)
* ​Eater of Worlds Relic(Dropped in Master Mode)

From any enemy in Hardmode:
* ​Corruption Key(1/2500 chance, only on )
* ​Corruption Key Mold(1/2500 chance)

From World Feeders:
* ​Cursed Flame
* ​World Feeder Kite(on Windy Days)

From Devourers and World Feeders:
* ​Suspicious Looking Apple

From Corruptors, Corrupt Slimes, Slimelings and World Feeders:
* ​Meat Grinder

From Corrupt Slimes, Shadow Slimes and Slimelings:
* ​Gel
* ​Blindfold

From Shadow Slimes:
* ​Petri Dish

From Corruptors:
* ​Vitamins

From Dark Mummies:
* ​Blindfold
* ​Dark Shard
* ​Megaphone
* ​Mummy set(rare)

From vegetation:
* ​Vile Mushroom
* ​Deathweed
* ​Deathweed Seeds(during Blood Moon)
* ​Ebonwood(from trees)

From terrain:
* ​Ebonstone Block
* ​Ebonsand Block(Desert)
* ​Purple Ice Block(Snow biome)

From fishing:
* ​Ebonkoi
* ​Purple Clubberfish
* ​Toxikarp(Hardmode only)
* ​Corrupt Crate
* ​Defiled Crate(Hardmode only)

From shaking trees:
* ​Blackcurrant
* ​Elderberry

For SaleFrom the Painter:
* ​Lightless Chasms

Music
* ​Corruption
* ​Corruption (Otherworldly)

### Underground Corruption contents

Characters
* ​Devourer
* ​World Feeder
* ​Cursed Hammer
* ​Shadow Hammer
* ​Clinger
* ​Corruptor
* ​Corrupt Slime
* ​Slimer
* ​Corrupt Mimic
* ​Corruption Pigron(While overlapping an Ice biome in Hardmode)

Corruption Underground Desert:
* ​Vile Ghoul

Unique DropsFrom Corrupt Mimics:
* ​Dart Rifle
* ​Worm Hook
* ​Chain Guillotines
* ​Clinger Staff
* ​Putrid Scent
* ​Greater Healing Potion
* ​Greater Mana Potion

From Corrupt Slimes and Shadow Slimes and Slimelings:
* ​Blindfold
* ​Gel

From Shadow Slimes:
* ​Petri Dish

From Cursed Hammers:
* ​Nazar

From Corruptors:
* ​Vitamins

From Devourers and Corruptors:
* ​Rotten Chunk

From Clingers, Corruptors, Corrupt Slimes, Cursed Hammers, Slimelings and World Feeders:
* ​Meat Grinder(Only on )

From Clingers, Devourers, Corruptors, Corrupt Slimes, Slimers and World Feeders:
* ​Monster Meat

From Devourers:
* ​Worm Tooth
* ​Tentacle Spike

From World Feeders:
* ​World Feeder Kite(on Windy Days)

From World Feeders and Clingers:
* ​Cursed Flame

From Devourers and World Feeders:
* ​Suspicious Looking Apple

From Shadow Hammers
* ​Mythril Bar
* ​Cobalt Bar
* ​Adamantite Bar

From any enemy:
* ​Corruption Key(1/2500 chance, only on )
* ​Corruption Key Mold(1/2500 chance)
* ​Soul of Night(1/5 chance)

From vegetation:
* ​Deathweed
* ​Vile Mushroom

From terrain:
* ​Ebonstone Block
* ​Ebonsand Block(Underground Desert)
* ​Hardened Ebonsand Block(Underground Desert)
* ​Ebonsandstone Block(Underground Desert)
* ​Purple Ice Block(Ice biome)

From fishing:
* ​Ebonkoi
* ​Purple Clubberfish
* ​Toxikarp
* ​Corrupt Crate(Pre-Hardmode only)
* ​Defiled Crate(Hardmode only)

Music
* ​Underground Corruption
* ​Underground Corruption (Otherworldly)
* ​Underground Crimson

## The Crimson

In contrast to the Corruption, the Crimson presents more of a red, gory theme, with red grass, stone, and foliage. Unique enemies that only appear in a Crimson world include Blood Crawlers, Face Monsters and Crimeras. The Brain of Cthulhu, the alternative to the Eater of Worlds, can only be summoned in the Crimson. Crimson-infected stone is called Crimstone, and like its Corruption counterpart, can only be mined with a Nightmare Pickaxe/Deathbringer Pickaxe or better. Like the Corruption, the Crimson contains deep chasms, but these are differently shaped: A winding tunnel from the surface leads to a large cavern, with secondary tunnels spreading downward from the cavern. These tunnels look quite like hands. While long falls are less of a hazard here, the area is still quite dangerous. Instead of Shadow Orbs, the Crimson contains Crimson Hearts, placed at or beyond the end of the secondary tunnels. Destroying a world's first Crimson Heart will drop The Undertaker with some Musket Balls, which, like their Corruption counterparts will fulfill the criteria for the Arms Dealer to arrive. Destroying three Crimson Hearts will result in the spawning of the Brain of Cthulhu.

### Crimson contents

CharactersPre-Hardmode:
* ​Blood Crawler
* ​Vicious Goldfish(Only on )
* ​Face Monster
* ​Crimera
* ​Brain of Cthulhu(boss)

Hardmode:
* ​Herpling
* ​Crimslime
* ​Blood Jelly
* ​Blood Feeder

Crimson Desert:
* ​Blood Mummy
* ​Dark Mummy

Unique TreasuresFrom Crimson Hearts:
* ​The Undertaker(Dropped with 100 Musket Balls)
* ​The Rotted Fork
* ​Crimson Rod
* ​Panic Necklace
* ​Crimson Heart (item)

Unique DropsFrom Blood Crawlers, Crimera and Face Monsters:
* ​Vertebra
* ​Tentacle Spike

From Blood Crawlers, Crimera, Face Monsters, Blood Feeders, Blood Jelly, Herplings and Crimslimes:
* ​Monster Meat

From Crimera:
* ​Burger

From Brain of Cthulhu:
* ​Crimtane Ore
* ​Tissue Sample
* ​Bone Rattle
* ​Brain of Cthulhu Trophy
* ​Brain of Cthulhu Mask
* ​Treasure Bag(Drops the Brain of Confusion in Expert Mode)
* ​Brain of Cthulhu Relic(Dropped in Master Mode)
* ​Brain in a Jar(Dropped rarely in Master Mode)

From any enemy in Hardmode:
* ​Crimson Key(from any enemy, 1/2500 chance, only on )
* ​Crimson Key Mold(from any enemy, 1/2500 chance)

From Herplings and Crimslimes:
* ​Meat Grinder

From Blood/Dark Mummies:
* ​Mummy set(rare)
* ​Blindfold
* ​Dark Shard
* ​Megaphone

From vegetation:
* ​Vicious Mushroom
* ​Deathweed
* ​Deathweed Seeds(during Blood Moon)
* ​Shadewood(from trees)

From terrain:
* ​Crimstone Block
* ​Crimsand Block(Desert)
* ​Red Ice Block(Snow biome)

From fishing:
* ​Crimson Tigerfish
* ​Hemopiranha
* ​Bladetongue(Hardmode only)
* ​Crimson Crate
* ​Hematic Crate(Hardmode only)

From shaking trees:
* ​Blood Orange
* ​Rambutan

For SaleFrom Painter:
* ​Deadland Comes Alive

Music
* ​Crimson
* ​Crimson (Otherworldly)

### Underground Crimson contents

Characters
* ​Blood Jelly
* ​Blood Feeder
* ​Crimson Axe
* ​Ichor Sticker
* ​Floaty Gross
* ​Crimson Mimic
* ​Crimson PigronWhile overlapping an Ice biome in Hardmode

Crimson Underground Desert:
* ​Tainted Ghoul

Unique DropsFrom Crimson Axes:
* ​Nazar

From Ichor Stickers:
* ​Ichor

From Floaty Grosses:
* ​Vertebra
* ​Vitamins
* ​Meat Grinder

From Blood Feeders, Blood Jelly, Floaty Grosses and Ichor Stickers:
* ​Monster Meat

From Crimson Mimics:
* ​Life Drain
* ​Dart Pistol
* ​Fetid Baghnakhs
* ​Flesh Knuckles
* ​Tendon Hook
* ​Greater Healing Potion
* ​Greater Mana Potion

From any enemy:
* ​Crimson Key(from any enemy, 1/2500 chance, only on )
* ​Crimson Key Mold(from any enemy, 1/2500 chance)
* ​Soul of Night(1/5 chance)

From vegetation:
* ​Deathweed

From terrain:
* ​Crimstone Block
* ​Crimsand Block(Underground Desert)
* ​Hardened Crimsand Block(Underground Desert)
* ​Crimsandstone Block(Underground Desert)
* ​Red Ice Block(Ice biome)

From Fishing:
* ​Crimson Tigerfish
* ​Hemopiranha

Music
* ​Underground Crimson
* ​Underground Crimson (Otherworldly)

## Spread

Main article: Biome spread
Both the Corruption and the Crimson will spread themselves, similar to the Hallow. This means that they slowly convert certain susceptible tiles that are in the vicinity of existing Corrupt/Crimson blocks. While their spreading capabilities are very limited during pre-Hardmode, they spread much faster and more aggressively after defeating the Wall of Flesh. Defeating Plantera for the first time reduces the overall spread speed of all three biomes by ~~50\*~~1/2 (50%).

### Corrupted and Crimson Deserts

Main articles: Corrupted Desert, Crimson Desert

The evil biomes can overlap deserts, and in Hardmode, can spread through them, creating Corrupted and Crimson deserts. In the Corruption, sand is replaced with Ebonsand, and in the Crimson, sand is replaced with Crimsand. Unique enemies not found in the normal Corruption and Crimson can be found in the biome's desert variant.

## Purification

See also: Guide:Maintaining world purity

In Hardmode, the Corruption or Crimson (like the Hallow) can spread out of control; without player efforts, the evil biome and Hallow will together take over the entire world.

In pre-Hardmode, players can use Purification Powder to purify small portions of the Corruption/Crimson, and Sunflowers to block spread of infected grass. However, it is not until Hardmode that the spreading biomes become a major issue.

In Hardmode, a good strategy is to dig 3-tile-wide tunnels around the Corruption/Crimson, containing it. However, near the surface Thorny Bushes can spread the Corruption up to 6 tiles, so the tunnels there need to be 6 tiles wide or lined with non-corruptible blocks.

Removing the Corruption or Crimson wholesale, or reversing its spread in Hardmode, effectively requires the Clentaminator. This can be purchased for 2 from the Steampunker, who arrives after at least one mechanical boss has been defeated. Using the Clentaminator with Green Solution (also purchased from the Steampunker) can purify large sections of the evil biomes. However, most players will want to keep some well-contained pockets of the biome, as the enemies there have unique drops (some of which are recommended to advance in the game).

The evil biomes are also blocked by the presence of the Hallow, and vice versa; even before obtaining the Clentaminator, seeding the Hallow is an alternate strategy to limit the spread of Corruption or Crimson. However, this may mean eventually having to deal with an out of control Hallow in the future.

## Tips

* On the PC, Console, Mobile, Old Chinese, tModLoader, and tModLoader Legacy versions, one-half of the world generation progress bar will be green, and the other half purple or red, depending on if the world is to have Corruption or Crimson. The step in world generation in which the Corruption is created is called "Making the world evil", and the step in world generation in which the Crimson is created is called "Making the world bloody". Also, a tree at the side of the world name in world selection has one green/normal side, the other purple/red (indicating Corruption/Crimson respectively). In Hardmode, part of the tree will be yellow, representing The Hallow.

## Trivia

* A drunk world always contains both evil biomes.