Terrestrial Warfare

This page mainly discusses the mechanics for fighting terrestrial wars. For a more detailed discussion about starting and ending wars, see Foreign Relations#Wars instead.

Wars begin when a councilor for the executive faction of one of two Rivals selects the War policy against the rival. All war-capable allies of the defending rival (with an army or nuclear weapons) join the war. All war-capable allies of the attacker are given the option to join on the attacker's side.

To win a war, an army must occupy the enemy's Capital region. At that moment, the war ends, triggering a regime change. Claimed regions change hands to the occupier and its allies. If any of the invaded nation remains, its control point owners are replaced with those of the victor. Some of the nation's stats change when a new regime is installed, sometimes in unpredictable ways, but the new ruling faction will be able to fund Direct Investments into the nation at greatly reduced Influence cost for a period of one year. Unoccupied Regions and surviving enemy armies will contribute to greater Unrest following a regime change.

Wars may also end with a simple peace where both sides return to the prewar status quo.

Armies

Armies represent multiple modern divisions that are capable of gaining and holding territory in other Nations. Control of an army is gained after councilors gain at least partial control of a nation. Most Nations don't have armies at the campaign start, but Nations with sufficient Population can build new ones with enough investment into the Build Army Priority. While powerful, armies are a drag on a nation's economic development and remain subject to the international relations of their home countries, which too can be managed with sufficient control of a nation.

Armies have a headquarters region in their home nation. If located there, they incur a smaller cost to the nation's economic development.

Armies rely on two key values: its parent nation's Miltech level and its strength. The strength value measures how much damage the army has taken. Armies usually passively and freely repair themselves when not fighting in a friendly region.

Some armies have a Navy upgrade that allows them to transit oceans. During wartime, a nation's navies can only cross the water if the nation has naval superiority over its foes. Only larger or wealthier Nations have the capability to build and project power with navies.

Naval Freedom

For each war, the game computes for each side the sum of the Miltech of the armies that have a navy upgrade. If one side has a higher sum than the other, then the other side of the war is blockaded: all of its nations no longer have Naval Freedom.

As a result, a nation only has Naval Freedom if it is not blockaded in any of the wars that it is involved in.

Notably, since wars can get very messy, with multiple overlapping wars, it is actually entirely possible for all nations to lose their Naval Freedom.

Consider a simple example with 3 nations: A, B, and C, such that:

• A has a single navy with 3 Miltech.
• B has a single navy with 2 Miltech.
• C has a single navy with 2 Miltech.

Suppose there are three overlapping wars X, Y, and Z, such that:

• War X pits A against B.
• War Y pits A against C.
• War Z pits A against B and C.

Then the result would be:

• War X blockades B, since A's 3 naval score beats B's 2 naval score.
• War Y blockades C, since A's 3 naval score beats C's 2 naval score.
• War Z blockades A, since A's 3 naval score is beaten by the combined naval score of B's 2 naval score added to C's 2 naval score = 4 naval score.

So all 3 nations have no Naval Freedom.

Army Movement

Armies are allowed to be in any region R such that one of the following is true:

• R belongs to the army's home nation.
• R belongs to a nation that is allied to the army's home nation.
• R belongs to a nation that is at war with the army's home nation.

An army can directly travel from any region R1 to any region R2 such that at least one of the following is true:

• R1 and R2 are adjacent.
• R1 and R2 are adjacent only for friendly armies, and both R1 and R2 belong to nation(s) that are not at war with the army's home nation.
• All of the following are true:
  • R1 and R2 both currently have world ocean access.
  • The army's home nation has naval freedom.
  • Either the army does not need to travel between the Black Sea and the World Ocean, or the army's home nation has access to the Turkish Strait.

A nation has Turkish Strait access as long as one of the following is true:

• It is not at war with the nation that owns the Istanbul region.
• The Istanbul region is fully occupied.

Land Movement

The time needed for an army to travel directly between two adjacent regions without using a navy is calculated as follows:

 Duration (days) = Distance (km) / 300 (km/day) * 4 / Miltech 

But this value is affected by the following multipliers:

Condition(s)	Multiplier Value When:
	Only Origin Region is Small	Only Destination Region is Small	Otherwise
Origin Region is not friendly OR Origin Region has enemy armies	5 ^ 0.2	5 ^ 0.8	5 ^ 0.5
(Origin Region is not friendly OR Origin Region has enemy armies) AND Origin Region is Rugged	1.5 ^ 0.2	1.5 ^ 0.8	1.5 ^ 0.5
Origin Region is friendly AND Origin Region has no enemy armies AND Origin Region is Rugged	1.25 ^ 0.2	1.25 ^ 0.8	1.25 ^ 0.5
Origin Region is friendly AND Origin Region has no enemy armies AND Origin Nation has >5 Unrest	(1 + (Origin Nation Unrest - 5) / 6.5) ^ 0.2	(1 + (Origin Nation Unrest - 5) / 6.5) ^ 0.8	(1 + (Origin Nation Unrest - 5) / 6.5) ^ 0.5
Origin Region is a Colony	1.5 ^ 0.2	1.5 ^ 0.8	1.5 ^ 0.5
Destination Region is not friendly	5 ^ 0.8	5 ^ 0.2	5 ^ 0.5
Destination Region is not friendly AND Destination Region is Rugged	1.5 ^ 0.8	1.5 ^ 0.2	1.5 ^ 0.5
Destination Region is friendly AND Destination Region is Rugged	1.25 ^ 0.8	1.25 ^ 0.2	1.25 ^ 0.5
Destination Region is friendly AND Destination Nation has >5 Unrest	(1 + (Destination Nation Unrest - 5) / 6.5) ^ 0.8	(1 + (Destination Nation Unrest - 5) / 6.5) ^ 0.2	(1 + (Destination Nation Unrest - 5) / 6.5) ^ 0.5
Destination Region is a Colony	1.5 ^ 0.8	1.5 ^ 0.2	1.5 ^ 0.5

Naval Movement

The time needed for an army to travel between two regions without using a navy is calculated as follows:

 Duration (days) = (14 days + Distance (km) / 792 (km/day) ) * 4 / Miltech 

But this value is affected by a number of complex calculations that consider the different possible sea routes. In particular, the duration can be significantly affected by whether the army's nation has access to the Suez and Panama canals.

A nation has canal access as long as one of the following is true:

• It is not at war with the nation that owns the Canal region.
• The Canal region is fully occupied.

The Canal regions are:

• Cairo for the Suez Canal.
• Panama City for the Panama Canal.

Army Battle

Simplified Combat Rules

Combat in Terra Invicta is a comparison of Miltech levels. Higher Miltech means you hit more often and deal more damage. If two forces have equal Miltech, the base hit chance is 50%.

1. Hit Chance (The Accuracy Gap)

The game calculates the difference (Δ) between the Attacker's Miltech and the Defender's Miltech.

If Miltechs are equal: 50% Hit Chance. If you have the advantage: Your hit chance climbs toward 100%. If you are outclassed: Your hit chance drops toward 0%.

   Hit Chance (Advantage)=100%−(50%×0.775)^(1.5×Δ)
   Hit Chance (Disadvantage)=50%×0.775^(1.5×Δ)

Hit Chance Reference Table

The following table shows the 1vs1 hit chance based on the Miltech difference (Delta = Attacker Miltech - Defender Miltech).

Miltech Difference (Delta)	Hit Chance	Note
+3.0	84.1%
+2.0	76.7%
+1.0	65.9%	Strong offensive edge.
+0.8	63.2%
+0.6	60.3%
+0.4	57.1%
+0.2	53.7%
0.0	50.0%	Even match; coin-flip odds.
-0.2	46.3%
-0.4	42.9%
-0.6	39.7%
-0.8	36.8%
-1.0	34.1%	Struggling to land hits.
-2.0	23.3%
-3.0	15.9%

2. Damage Formulas

Damage is calculated as a percentage of the defender’s Max Health.

Army vs. Army

When an army hits another army, it deals roughly 10% of its Miltech in percentage of defender’s Max Health.

   Base Damage: Miltech × 0.1 (±20%)

Variance: ±20% is the game simulating a damage range mechanic.

Critical Hit: Usually 1x. Increases to 3x if the attacker is at full health and the region is unoccupied (an "Ambush"), or by a small random chance based on the total number of armies in the fight.

Region vs. Army

Region defenses (fortifications/militia) fire every day at every hostile army. They deal less base damage but have much higher "Critical" lethality.

   Base Damage: Region Miltech × 0.0225

The "Lethality" Multiplier: If an army is at full health and the region is unoccupied, the region can deal a massive 100x damage critical hit.

Overwhelmed Defenses: If more hostile armies are present than friendly armies, the region's damage output is reduced.

Occupying a Region (Army vs. Region)

When an army hits region defenses, it increases the Occupation %.

   Base Damage: Army Miltech × 0.0225

Advantage Bonus: If your Army Miltech is higher than the region's base tech, you gain occupation faster.

Geography Modifiers: Occupation is slower in regions with huge populations (like Delhi) or massive land areas (like Siberia).

Crowding Penalty: Having too many armies in one spot (more than 1 per 100,000 km2) slows down occupation by up to 50%.

Combat Rules

Combat occurs whenever an army A is in a region R such that at least one of the following is true:

• A's home nation is at war with the home nation of another army in R.
• R is partially or fully occupied and A's home nation owns R.
• R is partially or fully occupied and A's home nation is allies with the nation that owns R.
• A's home nation is at war with the nation that owns R and R is not fully occupied.
• A's home nation does not exist and R is not fully occupied.

Alien-Related SPOILERS INSIDE!

There is a Megafauna Army in R that is not owned by the same faction that owns A. A's home nation is at war with the nation that owns R and A is an Invader Army and R is fully occupied by a war alliance that does not include the Alien Nation. A's home nation does not exist and A is an Invader Army and R is fully occupied by a war alliance that does not include the Alien Nation. A is a Megafauna Army that is owned by the Aliens and R is not part of the Alien Nation and R is not owned by a nation whose executive is controlled by a faction that has researched Xenofauna Harmony. A is a Megafauna Army that is owned by a faction F that is not the Aliens and every non-Megafauna army in R that is owned by F is owned by a nation that is at war with the nation that owns R.

Combat is simulated as a daily exchange of attacks. For each army A:

1. If there is an enemy army in the combat region, then A randomly selects one to fire at, preferring to avoid any armies owned by the same faction as A.
2. If A is within a region that is hostile to A, then:
   1. The region defenses fires at A.
   2. If A did not fire at anyone in the first step AND the region defenses missed its attack on A, then A fires at the region defenses.
3. Otherwise if A is within a region that is friendly to A and there is no enemy army in the region and the region is partially or fully occupied by another nation that is at war with the home nation of A and A is not performing an operation, then:
   1. The region defenses fire at A... which reduces their occupation instead of hurting A ??? (TODO: Someone dig through code to understand what's going on x_x)

Note that this means every army can fire at most one attack per day, but region defenses fire an attack on every hostile army every day.

Every attack has a hit chance that is determined by the gap between the attacker's Miltech and the defender's Miltech. But several modifiers may be applied to each side's Miltech, including but not limited to Advising Councilors, rugged terrain bonuses, and damage taken.

When attacks hit, damage is taken, which scales based on the attacker's Miltech. When armies take damage, their health % drops. When region defenses take damage, their occupation % increases.

If a region is fully occupied it ceases fighting, but it can't change hands until the war is concluded. Regional economies and space facilities can take significant collateral damage during fighting, although the rate of damage goes down as {Miltech goes up (representing more precise weaponry). Sufficient collateral damage will count as an atrocity by the army's owning faction.

Formulas

Miltech Calculations:

Factor	Army Miltech A	Army Miltech B	Region Miltech
Base Miltech	Base Miltech	Base Miltech	Base Miltech
Councilor Advise Bonus	+0.01 per	+0.01 per	+0.01 per
LEO Hab Bonus (capped at +0.3)	+0.03 per Military Lab	+0.03 per Military Lab	No Effect
In Home Nation	+0.2	+0.2	No Effect
In Home Nation AND region is rugged	+0.2	+0.2	+0.2
In Home Nation AND region is core economic	+0.1	+0.1	+0.1
Region is rugged and Mountain Warfare Doctrine is researched	+0.125	+0.125	+0.125
Region is core economic and Urban Warfare Doctrine is researched	+0.125	+0.125	+0.125
Army CP is disabled (Abandoned or Crackdowned)	-0.2	-0.2	No Effect
In Allied (or Home) Nation	+0.05 per Cohesion of Allied Nation	No Effect	No Effect
Home Nation's Cohesion	No Effect	No Effect	+0.05 per Cohesion
Home Nation's Unrest	No Effect	No Effect	-0.05 per Unrest
Adjacent Regions belonging to Same Home Nation	No Effect	No Effect	+Fraction of such Regions that are unoccupied and not fighting × Home Nation's Miltech × 0.1 × (1 - 0.05 × Home Nation's Unrest)
Remaining Combat Effectiveness	× (1 - 0.5 × Lost Health %)	× (1 - 0.5 × Lost Health %)	× (1 - 1/3 × Occupation %)

Note: If a nation has not completed the Found Military Priority, then its regions have effectively 0 Miltech for combat.

Hit Chance Calculation:

• When an army fires at another army, the attacking army uses its Army Miltech A as the Attack value, while the defending army uses its Army Miltech B as the Defense value.
• When region defenses fire at an army, the region defenses use Region Miltech as the Attack value, while the defending army uses its Army Miltech A as the Defense value.
• When an army fires at the region defenses, the hit chance is always 100%. (But the army only fires if the region defenses missed their attack.)

Condition	Formula
Defense ≥ Attack	50% × 0.775^(1.5 × (Defense-Attack))
Attack > Defense	100% − (50% × 0.775^(1.5 × (Attack-Defense)))

Damage taken: When an army successfully lands a hit on another army, the defending army loses X% of its max health, where X calculated as follows:

1. Set X to the attacking army's Army Miltech A.
2. Multiply X by 0.1.
3. Multiply X by a random value between 0.8 and 1.2.
4. Multiply X by a critical multiplier Z, calculated as follows:
   1. Set Z to 1.
   2. Y% chance to set Z to 3, where Y is the square of the number of armies in the region that are involved in the war (allied armies that aren't part of the war don't count).
   3. If the attacking army is at full health and neither army is a Megafauna and the region is 0% occupied, set Z to 3.
5. All army damage bonuses from Projects are applied to X. (These bonuses are multiplicative and compounding, but often require the defending army to be a specific type of army.)

When the region defenses successfully land a hit on an army, the defending army loses X% of its max health, where X calculated as follows:

1. Set X to the region's Region Miltech.
2. Multiply X by 0.0225.
3. Multiply X by a random value between 0.8 and 1.2.
4. Let Y be the number of region-friendly armies in the region that are involved in the war (allied armies that aren't part of the war don't count) multiplied by the square of the number of region-hostile armies in the region.
5. Multiply X by a critical multiplier Z, calculated as follows:
   1. Set Z to 1.
   2. Y% chance to set Z to 40.
   3. If the region is 0% occupied and the defending army is at full health, then set Z to 100.
   4. If Z is not 100, another Y% chance to set Z to 40.
   5. If Z is less than 40, (Y% / (100% - Y%)) chance to set Z to 5.
6. All army damage bonuses from Projects are applied to X, except for bonuses against Megafauna. (These bonuses are multiplicative and compounding, but often require the defending army to be a specific type of army.)
7. Let H be the sum of the Remaining Combat Effectiveness multipliers of every region-hostile army in the region.
8. Let F be the sum of the Remaining Combat Effectiveness multipliers of every region-friendly army in the region that is involved in the war (allied armies that aren't part of the war don't count).
9. If H - F is more than 0, then multiply X by 1 - (H - F) / (H - F + 2).
10. (1 - Region occupation % by defending army's home nation / H) chance to multiply X by 2.

If this last (1 - Region occupation % by defending army's home nation / H) chance fails, the region occupation % by the defending army's home nation actually decreases by D%, where D is calculated as follows:

1. Set D to the region's Region Miltech.
2. Multiply D by 0.0225.
3. Multiply D by a random value between 0.8 and 1.2.
4. Divide D by the number of region-hostile armies in the region.
5. Multiply D by the Region Combat Action Multiplier, which is calculated as 2 / (Region Population ^ 0.75 / Game Start Mean Average Region Population ^ 0.75 + Region Area ^ 0.5 / Median Region Area ^ 0.5).
6. If D > 10, then set D to 10.

When an army hits the region defenses, the attacking army's home nation increases its occupation % of the region by X%, where X is calculated as follows:

1. Set X to the attacking army's Army Miltech A.
2. Let G be X - the defending region's home nation's base Miltech - the Councilor Advise Bonus for the defending region's home nation.
3. If G > 0 then add G to X.
4. Multiply X by 0.0225.
5. Multiply X by a random value between 0.8 and 1.2.
6. Multiply X by the Region Combat Action Multiplier, which is calculated as 2 / (Region Population ^ 0.75 / Game Start Mean Average Region Population ^ 0.75 + Region Area ^ 0.5 / Median Region Area ^ 0.5).
7. Multiply X by a critical multiplier Z, calculated as follows:
   1. Set Z to 1.
   2. Y% chance to set Z to 40.
   3. If the region is 0% occupied and the attacking army is at full health, then set Z to 100.
   4. If Z is not 100, another Y% chance to set Z to 40.
   5. If Z is less than 40, (Y% / (100% - Y%)) chance to set Z to 5.
8. Let C be the number of region-hostile armies in the region - the region area / 100000km².
9. If C > 0, then multiply X by Max(1 - C * 0.02, 0.5)
10. If X > 10, then set X to 10.

Army Operations

The faction that controls an army can conduct operations with it. They are:

Operation	Effects
Deploy Army	Move this Army to an adjacent region, including those of allies or wartime enemies. Armies will engage in battle with enemy armies and occupy enemy regions.
Deploy Armies	Move all stacked armies to an adjacent region, including those of allies or wartime enemies. Armies will engage in battle with enemy armies and occupy enemy regions.
Assault Alien Asset	Launch an assault on a fixed alien target.
Assault Space Facility	Destroy a fixed space facility in the region.
Raze Region	Launch a general attack on economic and civilian targets in this region. Commits 5 to 25 atrocities.
Airlift Home	Return this army to its home region during peacetime. Operation will not complete if home nation is at war.
Cancel Operation	Cancel current operation for this Army. Army will resume fighting if enemies are present.

Wiki Help wanted: Look up the in-game image and description for the Army Annex Region operation and upload both here!

Annex Region

The game mechanics for army annex operations are explained here Foreign Relations#War_Annexation.

Raze Region

See Regions#Region_Damage.

Assault Alien Asset

Damage Taken by Armies when they Assault Alien Assets

Mission Outcome	Type of Alien Asset
	Xenoflora	Other
Critical Failure	(30% to 150%) / Base Miltech	(150% to 300%) / Base Miltech
Normal Failure	(15% to 112.5%) / Base Miltech	(75% to 225%) / Base Miltech
Normal Success	(0% to 75%) / Base Miltech	(0% to 150%) / Base Miltech
Critical Success	(0% to 15%) / Base Miltech	(0% to 30%) / Base Miltech

Note: Base Miltech is simply the army's home nation's Miltech, with all modifiers ignored.

See Aliens for spoilers on the different types of alien assets that can be assaulted, as well as the consequences of such assaults.

Army Healing

An injured human army will passively heal over time when all of the following conditions are true:

• It is in a friendly region.
• The region is currently not occupied or being occupied.
• It is not in battle with other armies.
• It is not currently performing an operation.

The % health that gets healed each day is calculated as follows:

1. 0.5% Base.
2. +0.5% more if the faction that controls the army also controls the Defense Sector Control Point of the army's home nation.
3. +0.5% more if the army is in its home nation.
4. +0.5% more if the army is in its home region.
5. Multiply the total by (1 - (Currently Healing Human Armies of Home Nation / (Total Human Armies of Home Nation + 1))).
   • Note: This step is currently bugged to never occur.
6. +0.5% more if the faction that controls the army has researched the Rapid Repairing Materials project.
7. +0.5% more if the faction that controls the army has researched the Predictive Logistics Systems project.

Alien-Related SPOILERS INSIDE!
Human armies that are owned by the Aliens still follow the same healing rules. But for the healing mechanics of Alien-related armies, see Aliens#Megafauna and Aliens#Invader_Armies instead.

Army Death

Whenever an army dies, multiple effects may occur:

Democracy Penalties

If the dead army belonged to a democratic human nation, then that nation suffers two penalties:

• A Cohesion loss equal to the nation's Government / 10.
• Applies Propaganda in the nation for the faction that owned the dead army. Propaganda strength is equal to (0 - the nation's Government).

Army IP Refund

Whenever a human army dies, its home nation receives a fraction of its IP Cost as a refund. This refund is put directly into the Build Army Priority and/or Build Navy Priority, so it can often result in new Armies and/or Navies being built the next day. Specifically, the refund amounts are calculated as follows:

Refund Amounts for Build Army Priority. Only applies if army did not die by nuke.

Army Died in Home Nation?	Refund Amount
Yes	(30% to 50%) of Build Army Priority cost.
No	(15% to 25%) of Build Army Priority cost.

Refund Amounts for Build Navy Priority. Only applies if the dead army had a navy.

Army Died in Home Nation?	Home Nation has Naval Freedom?	Army Died in Region that currently has World Ocean Access?	Refund Amount
Yes	Yes	Yes	(70% to 90%) of Build Navy Priority cost.
Yes	Yes	No	(90% to 110%) of Build Navy Priority cost.
Yes	No		(20% to 30%) of Build Navy Priority cost.
No	Yes	Yes	(60% to 80%) of Build Navy Priority cost.
No	Yes	No	(80% to 100%) of Build Navy Priority cost.
No	No		(10% to 20%) of Build Navy Priority cost.

Complete Milestones

If the army is related to the Aliens in any way, then the faction that kills it may achieve certain milestones from doing so. See Aliens for details.

Hate Vent

See Diplomacy#Alien_Hate_Vent.

Nuclear Warfare

Some nations have a number of Nuclear Weapons available to them. These represent launching multiple strategic nuclear weapons at a target region. Launching nuclear strikes will devastate the economy of a region and the enemy Armies within it, although the damage will be somewhat mitigated if a nation is launching strikes on its own or an ally's territory. Launching factions will be charged with committing one or more atrocities. Detonating a sufficient number of nuclear weapons may also have disastrous global effects. A region with space defenses cannot be attacked with Nuclear Weapons.

Nations can develop nuclear weapon with the Develop Atomic Bomb Priority, which also gives 1 Nuclear Weapons. A nation with nuclear weapon program can build more with the Nuclear Weapons Priority.

Nations construct nuclear weapons as a deterrent to enemy invasion. Attempting to conquer a nuclear-armed nation will almost certainly lead to nuclear strikes in retaliation.

Valid Targets for a Nuclear Strike

Nukes can only be fired at Regions. The set of regions that a nation X can fire a nuke at is computed as follows:

1. Add every region that is owned by any nation that is at war with X.
2. If X does not have a spaceflight program, then remove every region that is not adjacent to X and does not have ocean access.
3. If X does not have a spaceflight program and does not have naval freedom, then remove every region that is not adjacent to X.
4. Add every region owned by X or an ally of X if the region currently contains an army that is owned by any nation that is at war with X.
5. For every region R, remove R unless one of the following is true:
   • R is owned by X.
   • R is owned by an ally of X.
   • R is owned by a nation that is at war with X and R does not have Space Defenses built.

Effects of a Nuclear Strike

Launching nuclear weapons will do terrible and lasting damage to the targeted region, destroy any enemy Armies and all space facilities, and surely be seen with horror around the globe.

Effects of a Nuclear Attack (In Chronological Order)

Category	Amount for Offensive Nukes	Amount for Defensive Nukes	Modifiers
Target Region GDP	-52.5% to -87.5%	-15% to -25%	Urban Armoring multiplies amount by 0.8. Civil Defense Programs multiplies amount by 0.8.
Target Region Population	-18.75% to -31.25%	-1.875% to -3.125%
Target Nation Pollution Multiplier	+0.075 to +0.125	+0.00375 to +0.00625	Multiplied by region's share of national GDP
Nuking Faction Commits Atrocities	1 per 100k Population killed (rounded down).		Multiply by 10 if nuke launcher is not on the defending side of any war where the target nation is on the attacking side. ...seems to apply for self-nukes too?? Alien-Related SPOILERS INSIDE!   Does not apply if the target region is owned by the Alien Nation. Capped between 1 and 20.
All Human Nations' GDP	-25% × region's share of global GDP + (0% to -2%)	-5% × region's share of global GDP + (0% to -2%)	None
Family Ties Trait Effect	-10 Loyalty		Multiply by 2 if Councilor's Faction launched the nuke.
Target Region is Core Economic	Remove Core Economic status	Nothing	None
All Human Nations' GDP	-2.5% + (0% to -2%)	N/A	If Target Region just lost Core Economic status.
Target Region is Core Oil or Core Mining	Remove Core Oil or Core Mining status	Nothing	None
All Human Nations' GDP	-1.5% + (0% to -2%)	N/A	If Target Region just lost Core Oil or Core Mining status.
Target Nation Priorities	Set to 0		Except Spoils, Unity, and Oppression.
Destroy Space Assets in Target Region	All Boost, Mission Control , and Space Defenses		If Target Nation is NOT Nuke Launcher
	N/A	All Boost and Space Defenses, just 1 Mission Control	If Target Nation is Nuke Launcher
Target Nation Funding	-50% × region's share of national GDP		If Target Nation is NOT Nuke Launcher
Health of Each Army in Target Region	Instant Death		For the Strongest Army that is not Ally of Nuker.
	Min(0%, (-100% + (1% to 5%) × (Base MilTech - 3.79)) × 0.140625)		For each Alien Invader Army that is not Ally of Nuker.
	Min(0%, -100% + (1% to 5%) × Max(0, Base MilTech - 3.79) × 0.75 if Army Nuclear Hardening researched × 0.140625 if working for Aliens)		50% chance for each Human army that is not Ally of Nuker.
	-100% × 0.75 if Army Nuclear Hardening researched × 0.140625 if working for Aliens		The other 50% chance for each Human army that is not Ally of Nuker.
	Min(0%, -100% + (1% to 5%) × Max(0, Base MilTech - 3.79))		50% chance for each Megafauna army.
	-100%		The other 50% chance for each Megafauna army.
	-100% / (48 to 52)		For each army that is Ally of Nuker.
Each Councilor in Target Region	50% Chance to die		Survivor trait gives immunity.
Alien Xenoforming	Set to 0 Xenoflora Growth Levels		None
Add Aerosols	0.00777		Multiply by Region Area (km²) / 10000km² if Region is an Island smaller than 10000km².
Target Region Gains 1 Layer of Nuclear Fallout

Orbital Bombardment

Spaceships with certain weapon modules can bombard hostile armies from orbit.

See Fleets#Orbital_Bombardment for more details.