War in the galaxy is not declared lightly. Factions weigh their military strength, past defeats, diplomatic history, and strategic opportunities before committing to hostilities. Understanding how the AI approaches war will help you prepare and respond.
War Declaration
AI factions consider several factors before declaring war: their aggression level, the relationship score (must be below -20), relative fleet power, recent defeats, and their combat track record against you. A faction that has been beaten repeatedly will be reluctant to attack again. Factions with no military will never declare war, and those significantly weaker than their target are very unlikely to.
Fleet Power Matters
Factions constantly assess the military balance. An AI with double your fleet power is far more likely to declare war, while one with less than half your strength will almost never attack. Building a strong fleet is the best deterrent against aggression. Factions will also comment on your military strength — friendly factions may warn you to build more ships, while hostile ones may mock your weakness or grow nervous about your power.
War Cooldowns
- After signing a peace treaty, a 20-turn cooldown prevents re-declaration of war.
- Wars last a minimum of 8 turns before either side can propose peace.
- After losing a war, factions wait at least 25 turns before re-declaring against the same enemy.
- Each consecutive war against the same faction increases the cooldown before the next one.
AI War Behavior
When at war, AI factions actively send combat fleets to attack your systems, bombard your colonies to reduce population, and launch ground invasions with troop transports. They prioritize undefended colonies and weak points in your territory. The more aggressive the faction, the more relentlessly they will press the attack.
Suing for Peace
AI factions propose peace when war exhaustion builds up, when they are losing battles, or when your fleet clearly outmatches theirs. Highly aggressive factions are much less likely to sue for peace and will fight longer before considering it. A faction that has lost many battles against you will be more willing to negotiate.