Slavery and Emancipation

Taking slaves

• Destroying a stack of 9: 60% chance of a slave.
• 7 or more units: 50%. 4 or more: 35%. 3 or fewer: 20%.
• Against barbarians, every chance is 10% higher.
• The slave goes to your city nearest the battle. It counts as a citizen there.
• Taking a city always brings home 1 slave, plus a 2.5% chance of another for every citizen it had, whether you keep it, raze it or it is destroyed in the taking. They go to your nearest other city. Retaking a city of your own brings none.
• Slaves can be moved to another of your cities for gold, by clicking the slave badge on the city's banner (or the slave count on the city screen): 10 plus 2 per tile of distance, the whole raised 5% for every city in your empire.

Riots and revolts

• Every slave in a city adds 1% to its chance, each turn, that the slaves rise: a city with 3 slaves risks 3% a turn.
• Slave riot: the slaves stop working (the free citizens carry on) and the city's defenses fall to nothing. It lasts 4 turns per slave.
• A fighting unit in or next to the city can put a riot down at once, at the cost of one slave.
• Slave revolt: when a city holds more slaves than free citizens, the rising is a revolt. The slaves stop working, the defenses fall, and if nobody puts it down within 5 turns the garrison is killed and the city goes over to the barbarians, who raise defenders of your own era to hold it.
• Putting down a revolt means a battle: one rebel per slave (up to 9) gathers beside the city, the first 3 with hand weapons and the rest with bows if you have them. The battle settles it: win, and one slave is killed and the revolt is over; lose, and the city goes over to the barbarians at once, the surviving rebels its new garrison.
• Once a riot or revolt is over, the city's defenses take 5 turns to come back.

Freeing slaves

• The policy decides whether battles bring slaves home. Unslotting it frees nobody: the slaves you hold stay, with all their risks.
• Slaves can be freed for gold from the slave count beside a city's population: 300 each, raised 5% for every city in your empire. They stay in the city as free citizens.
• A city frees only one slave a turn.
• No slave is freed while the Slavery policy is slotted: unslot it first (adopting it again costs culture).
• No slave is freed in a city whose slaves are in a riot or revolt: put it down or wait it out.
• The Emancipation wonder frees all of its builder's slaves at once, and bars the policy for good. While it stands, every slave in any other empire costs its city 1.
• A city you conquer keeps its slaves, and they are yours now, policy or not (they share the city's losses in the fighting). If you hold the Emancipation wonder they go free instead, and you gain 2 integrity for each such city. Barbarians keep no slaves: a city they take is freed.