Multiplayer (Civ6)

Multiplayer allows you to play Civilization VI with or against friends and strangers (and possibly AI opponents). The game host will decide every setting, including the map, the speed, the starting era, and which players, if any, will be on teams.

General multiplayer tips

Never trust anyone: Don't expect any pity, especially from strangers. Warmongers are prevalent online, and are way smarter than AI opponents. A cunning player may, for example, propose that you give them all the Gold in your treasury in exchange for most of their strategic and luxury resources, only to declare war on you the following turn. This ends the deal and leaves you unable to purchase units, while giving your opponent lots of Gold to spend. You should also make sure you have a large enough military to defend yourself on all fronts - if you use your entire army and navy to attack your neighbor, another opponent might launch an attack on you while your territory is undefended. It's also advisable to ask for friendship with players of whom you're suspicious, which will prevent them from declaring or joining wars against you.
Watch your treasury: Gold can be used to purchase units or levy them from city-states, which will give you a much stronger defense and more options in wartime. Always keep some on hand for emergencies.
Improve your cities' yields: You'll need Food to grow your Population, work more hexes, and build more Districts in your cities. You'll need Production to quickly construct buildings and wonders and train units. You never want to have the lowest Science output; your development will be slowed, you'll be easy prey for warmongers, and if even if you survive, you'll eventually lose diplomatic influence (since other players will have less trouble completing quests for city-states and you won't have a strong enough military to protect your interests). Which one(s) you focus most on improving will, of course, depend on your civilization, leader, and overall strategy.
Don't overextend yourself: Expanding to a continent another player controls will most likely cause him or her to go to war with you and take your cities, and it will be nearly impossible to transport your army there quickly enough to protect them. The one possible exception to this rule is an island city, which generally doesn't anger opponents as much and will provide you with a good base for aircraft, building or repairing ships, and staging invasions late in the game (especially if it has an Aerodrome with an Airport to allow airlifting). The Loyalty mechanics in the expansions make this doubly important, since cities close to an opponent's territory will lose Loyalty and eventually flip .
Team up if you can: When everyone can declare war on you, launch nuclear weapons at your cities, or conspire against you, having allies is more valuable than ever. It means no declarations of war, no spying, and maybe even alliance bonuses for 30 turns. Be wary, though - the closer you get to victory, the harder it will be to find players willing to ally with you.
Slow your opponents down as much as possible: Remember what your opponents' strengths are, and do your best to deny them what they need. Are you neighbors with Scythia or Mongolia? Don't trade them any Horses. Is another player missing a strategic resource you have? Keep it, unless that player offers to trade you another resource you need or something similarly generous. Is another player closing in on a Science Victory? Have Spies perform Disrupt Rocketry missions, nuke his or her Spaceports, or go to war and pillage them. Whenever possible, declare war on a player who's becoming too powerful or getting close to winning by any means - even if you can't wipe him or her out, you'll stop that player from trading with you and possibly force him or her to waste valuable time and resources fighting you off.