Land warfare

Version

This article has been verified for the current PC version (3.10) of the game.

War

Warfare

Space warfare

**Land warfare**

Wars are not decided only in space. In order to capture enemy worlds, entire armies are needed, along with the preparation and battlefield awareness to properly use them. However, worlds may only be invaded if the system's starbase has been occupied.

## Orbital bombardment

Orbital bombardment occurs when a fleet is in orbit around a hostile world and causes damage to any armies but also kills pops and causes  devastation. Effectiveness is based on the fleet size of the fleet in orbit, although it suffers diminishing returns after 100, and planet size, with every 10 planet size halving damaged from bombardment. The more pops and buildings a world has, the more damage it receives from orbital bombardment. Assault armies take double damage from orbital bombardment.

If orbital bombardment destroys the last army, the world has a chance to surrender if the attacking empire has the *Allowed* Orbital Surrender Acceptance policy. Worlds from  Gestalt Consciousness empires will never surrender.

Orbital bombardment damage dealt to enemy planets can be increased by the following:

Orbital bombardment damage taken from enemy fleets can be reduced by the following:

## Combat

Ground combat takes place between the world owner's armies and the invader's armies. It takes 10 days for armies in orbit to land on a world. The number of armies that can be engaged in combat on either side is five plus one-fifth of the  planet size. Excess armies are initially placed in a reserve area behind the frontline and replace any disengaged or destroyed armies as combat progresses.

Each day, each army engaged in combat deals its health and morale damage to a randomly selected enemy army; armies with less than 50% health are twice as likely to be selected. Armies below 50% health may also *disengage* from battle; this moves them from the frontline area to the reserve area. Disengaged armies cannot return to the frontline but can still be attacked by enemy armies and destroyed. Disengaged armies are half as likely to be selected as the target of an enemy army.

Unless an army is immune to morale damage, when its morale drops below certain thresholds, the army will be negatively affected with the following modifiers:

After 30 days, the attacker can choose to retreat at any time. However, there is a chance that each retreating army is destroyed while attempting to return to space, with the chance increasing as the army is more damaged. This makes retreating a risky endeavor and something to do only in very poorly chosen engagements.

As long as the ground combat is ongoing, it is possible for either side to land reinforcements, though typically this will only be feasible for the attacker. The ground combat ends when the attacker retreats or all armies of either side are destroyed.

### Army rank

 Experienced | 100 – 1000
 Veteran | 1000 – 10000
* **+20%** Morale
 Elite | ≥ 10 000
* **+40%** Morale
* **+20%** Health

As armies fight battles, they will increase in rank, improving their stats based on their experience points. Armies get **+2** experience points each time they deal damage and **+1** when they take damage. Army starting experience can be increased by **+100** by each of the following:

* Strength of Legions civic
* Private Military Companies civic
* Military Academy building
* Dread Encampment building
* Mercenary Liaison Office Corporate holding
* Pirate Free Haven corporate holding

### Army stat modifiers

In addition to army rank, several technologies, civics, species and leader traits, and other sources affect army damage, health, and other stats. Additionally,  Commanders provide  **+5%** army damage per level and plus other bonuses from traits. Modifiers from species traits affect armies recruited from that species, while  Commander and  Official traits affect armies led by that general or on world's in that governor's sector.

## Defense armies

Defense armies are automatically recruited by certain jobs, based on the species working that job, and can be organic or robotic. Defense armies cannot be moved from the colony they are recruited on and are used only to defend against enemy armies. While they are stronger one-for-one than assault armies, their loss does not cause  War Exhaustion and they do not cause  Collateral Damage, their limited recruitment means that significant investment is necessary to fend off a concentrated attack.

The type of army recruited depends on the pop working the building that spawns them. Defense armies do not incur any upkeep beyond that of the building and pop which creates the army.

### Pre-FTL armies

Pre-FTL armies are only used by primitive civilizations. They are weaker than any army and even the strongest Pre-FTL army can easily be defeated by an equal number of any regular army.

## Assault armies

An empire can recruit assault armies from a colony based on the species living there. The species must not have  *Exempt* Military Service rights in order to recruit an army from that species. An empire cannot recruit more assault armies from a species than the total number of pops of that species living in the empire, with the exception of  Clone Armies. Armies not tied to a species, such as the  Xenomorph Army, are unlimited unless otherwise specified.

Unlike defense armies, assault armies are based primarily in space and each recruited army boards a *transport ship*. Transport ships are unarmed but automatically upgraded with the latest defense and utility components. Assault armies can also be ordered to land on any controlled world to provide additional defense against invasion.

## Devastation

Devastation is a measure of how much damage has been caused to the colony's infrastructure. It goes from **0** to **100%**, and every **1%** Devastation causes a **1%** decrease in  housing,  amenities,  trade value,  resources from jobs,  upkeep from Jobs,  growth speed and  immigration pull. Pops will not migrate to a world that has at least **10%** Devastation.

Devastation is primarily caused by orbital bombardment, and to a lesser degree assault armies. Assault armies have a **Collateral Damage** modifier that determines how fast they cause devastation. It is reduced by half if the assault army is garrisoned on the world.

Devastation decreases by **0.05%** daily if the colony is not being invaded or bombarded.