Treaties and Trade Deals

Treaties

• Open Borders: each side's units may enter the other's territory. Only the side proposing it needs Writing. The other side needs nothing. Stands until one side cancels it. While it stands it is worth +1 integrity to both, growing by 1 every 15 turns up to +4; cancelling it costs -10 and loses what it had grown to.
• Peace Treaty: ends a war and binds both sides for 20 turns, during which neither may declare war on the other. Cancelling it early costs -20 integrity. Attacking through it costs a further -25 on top of the declaration.
• Surrender: a peace treaty offered from a position of weakness. It binds like a peace treaty.
• Peace with an AI leader may cost gold, at once or as tribute paid every turn for 40 turns, longer than the treaty itself. A new war between the two ends the tribute at once. A leader who started the war with you, or who still resents you, names a price when they refuse: it grows with how well the war is going for them, how much they resent you and how full your treasury is, and never exceeds what you could pay. A leader losing the war makes peace for nothing.

Trade deals

A trade deal exchanges goods and gold per turn with another civilization for a fixed term. The proposer's caravan carries it. The goods you give travel out to the partner's chosen city and what you receive comes back along the same route, so a deal needs a free caravan and a route a caravan can travel between the two cities (overland, or over water with Sailing and Maritime Trade).

• A deal runs 50 turns. In its last 5 turns either side may propose renewing it. Otherwise it lapses.
• Any number of deals may run between the same two civilizations. Each needs its own caravan.
• An AI leader's price depends on its mood towards you. It wants what it receives to be worth 1x what it gives when Friendly, 1.5x when Pleased, 2x when Neutral and 3x when Angry. A Furious leader will not trade at all.
• A city may be traded too (never a capital, nor a civilization's last city). It changes hands the moment the deal is signed, with its buildings and citizens intact. An AI leader parting with a city counts goods and gold paid by the turn at 50% of their worth, since those can be cancelled and the city cannot be taken back.
• A side that knows Mapmaking may give its map of the world. The other side learns every tile on it, once, when the deal is signed. Put both maps in for an exchange.
• When an offer comes to you, choose which of your cities their caravan calls at. What they give arrives there, and what you give leaves from there. Building an offer, each side's city is chosen above its column.
• Each side may give up to 3 kinds of item and 4 copies of any one good, plus gold. Any amount at once, up to what it holds, and as much per turn as its income and treasury can keep up for the 50-turn term.
• To demand tribute, offer nothing and ask only for gold at once. The Demand button puts it to them as a demand, as an AI leader does to you. An AI pays only a civilization that outguns it, and resents it either way.
• Everything a side receives arrives in one city, which keeps one copy of each good (none, if it already has that good) and may pass the spares on to your other cities by caravan.
• Signing a deal is worth +1 integrity to both; while it is in force a further +1; seeing it out +1. Cancelling early -5. War ends every deal between the two sides.
• Cutting the route with the Pirate order ends the deal for both sides.
• An AI leader weighs what they get against what they give and expects to come out well ahead. A Happy or Friendly leader asks for less, and one who thinks little of your reputation will not deal at all.