Under-City

Not to be confused with the Under-City building.

Under-Cities are a special settlement type available to Skaven factions which can be established secretly underneath settlements owned by other factions. They are similar to the Pirate Coves of the Vampire Coast.

Under-Cities were added in the Doomsayers Update, due to popular community demand.

How they work

• Under-Cities can be established by choosing the Expand Under-Empire settlement option after defeating a settlement's garrison.
• Additionally, Warlock Engineers can establish Under-Cities as a hero action, without needing a battle. There will be a 10-turn cooldown before any engineer can perform this action again, and the gold cost will increase with each under-city established in this manner. This includes the under-city with Warlock Laboratory established by a
• Under-Cities will be destroyed by razing the settlement entirely.
• Under-Cities have their own buildings available for construction, separate to regular Skaven buildings.
• Under-Cities have no garrison.

Discoverability

• Under-Cities and the buildings they construct are invisible to all other factions as long as they are not discovered.
• Most buildings in an Under-City increase the discoverability rating.
• Settlement owners can also construct buildings to increase discoverability.
• Certain heroes have the Discover Under-city passive ability, which will increase discoverability when such heroes are present in the region. Conversely, the under-city owner can deploy warlock engineers, which have the Conceal Under-city passive ability, in the region to decrease discoverability.
• The higher the discoverability, the more likely the Under-City is to be discovered.
• If discoverability reaches 100, it will be discovered. The settlement owner can then spend gold to destroy the under-city.

Buildings list

Annexation - Warren

Name/Tier	Cost/ Construct Time	Upkeep (per turn)	Discoverability	Effects
Burrows I	1000 G 1 Turn	None	+10	Upgradable into Dens Skaven Corruption +0.25 in adjacent provinces Player's local armies Campaign Movement +10% (when starting turn in region) Leadership +2 (when attacking) Replenishment rate +10% The Menace Below +2 uses
Dens II	2000 G 2 Turns	None	+20	Upgradable into Lairs Skaven Corruption +0.25 in adjacent provinces Player's local armies Campaign Movement +20% (when starting turn in region) Leadership +4 (when attacking) Replenishment rate +15% The Menace Below +3 uses
Lairs III

Annexation - Stronghold

Name/ Tier	Cost/ Construct Time	Upkeep (per turn)	Discoverability	Effects
Underpass I	1000 G 1 Turn	None	+10	Upgradable into Underway Junction Skaven Corruption +0.25 in adjacent provinces Player's local characters Hero Action success chance +10% Player's local armies Campaign Movement +10% (when starting turn in region) Attribute: Vanguard Deployment

Ruination

Name/ Tier	Cost/ Construct Time	Upkeep (per turn)	Discoverability	Effects
Rat King I	1000 G 1 Turn	-5 Food	+140	Skaven Corruption +0.25 Upgradable into The Vermintide
The Vermintide V	4000 G 5 Turns	-5 Food	+140	Upon Completion, the Under-city is destroyed and a Vermintide army under the player's control is spawned at the settlement. War will be declared between the player and the settlement owner if they are not already at war.
Makeshift Workshop I	1000 G 1 Turn	-500 G -2 Food	+160	Available to Clan Skryre only Skaven Corruption +0.25 Upgradeable into Doomsphere

• Doomsphere: razes the settlement above after 15 turns of building. (need to be playing as clan skrye which available in the Prophet and the Warlock DLC)
• Grand Plague Cauldron: An unending plague will be unleashed upon building completion, blighting all above until the Under-City is destroyed. (Clan Pestilens exclusive)

Concealment

Name/ Tier

Food

Money

Mining