Underground Contagion (Avalon)

File:BiomeBannerUndergroundContagion (Avalon).png

The Underground Contagion is a biome. It is the underground version of the surface-level Contagion, appearing at and below the cavern layer. Just like the surface Contagion, it is mainly composed of Chunkstone and spreads to nearby tiles. Although it is available in pre-Hardmode, most of its exclusive contents will only appear during Hardmode. After the Wall of Flesh is defeated for the first time, a diagonal stripe of Contagion is generated, creating additional Underground Contagion biome.

The Underground Contagion does not suppress the spawn of other underground and cavern enemies. During Hardmode, all enemies killed in the Underground Contagion have a 20*1/5 (20%) / 36*9/25 (36%) chance to drop a Soul of Night.

Note: Most characteristics of the surface Contagion also apply to the Underground Contagion. See The Contagion for more extensive information.

Contents

Characters

Pre-Hardmode:

• ​Bactus
• ​Contaminated Goldfish
• ​Pyrasite
• ​Bacterium Prime(boss)

Hardmode:

• ​Viris
• ​Infected Pickaxe
• ​Cougher
• ​Ickslime
• ​Contagion Mimic
• ​Contaminated Ghoul(Contagion Underground Desert)
• ​Contagion Pigron(Contagion Ice biome)

Unique Drops

From Contagion Mimics:

• ​Dart Shotgun
• ​Infection Hook
• ​Hemorrhaging Halberd
• ​Outbreak
• ​The Pill
• ​Greater Healing Potion
• ​Greater Mana Potion

From Ickslimes:

• ​Vitamins
• ​Gel

From Infected Pickaxes:

• ​Nazar

From Bactus, Pyrasites, and Viris:

• ​Yucky Bit

From Bactus, Ickslimes, and Viris:

• ​Monster Meat

From Virilings, Coughers and Contaminated Ghouls:

• ​Pathogen

From Pigrons:

• ​Bacon
• ​Ham Bat
• ​Pigron Kite(on Windy Days)
• ​Pigron Minecart

From Contaminated Ghouls:

• ​Ancient Cloth
• ​Dark Shard

From any enemy:

• ​Contagion Key(1/2500 chance
• ​Soul of Night(1/5 / 9/25 chance)

From vegetation:

• ​Barfbush
• ​Virulent Mushroom

From terrain:

• ​Chunkstone Block
• ​Snotsand Block(Underground Desert)
• ​Hardened Snotsand Block(Underground Desert)
• ​Snotsandstone Block(Underground Desert)
• ​Yellow Ice Block(Ice biome)

From fishing:

• ​Ickfish
• ​Sickly Trout
• ​Anchor Whipworm(Hardmode only)
• ​Contagion Crate(pre-Hardmode only)
• ​Plague Crate(Hardmode only)

From Angler Quests:

• ​Snotpiranha

Music

• ​ Underground ContagionFile:Music-Underground Contagion (Avalon).mp3

Gallery

Backgrounds

• 

  Rocky chunkstone wall with holes scattered on the surfaces

• 

  (Contagion Ice) Smooth yellow ice wall

See also

• Underground Corruption
• Underground Crimson
• Underground Hallow

History

• 1.2.4: Underground contagion desert enemies now spawn correctly.
• 1.2.3: Underground background now fades in and out at certain heights, instead of displaying all the way to the surface and lava layers.
• 1.1.3: Souls of Night can no longer drop in pre-Hardmode.
• 1.0.0: Introduced.