Three ages, seven cards each. Take one, pass the rest — and watch what your neighbours are collecting, because you will be buying stone from them all game. Build a city of quarries, temples, barracks and libraries, raise your wonder stage by stage, and count the shields on either side of you before Age III ends. 3–8 players, peer-to-peer: no accounts, no server, just a room code. Short of players? Add bots.
Three Ages, six turns each. You are dealt seven cards. Everyone chooses one at the same time, all the choices are revealed together, and the rest of the hand passes on — left in Age I, right in Age II, left again in Age III. After six turns the seventh card is thrown away unplayed.
Three things you can do with a card. Build it into your city if you can pay for it; slide it face down under your wonder board to complete the next stage (the card itself is spent, whatever it was); or sell it back for 3 coins. Sold cards, and the seventh card nobody gets to play each Age, go face down on a shared discard pile — which a few things can reach into. Halikarnassos does it, and so do Solomon and the Forging Agency: take the pile, look through it, build one card out of it for nothing, and put the rest back without showing anyone.
Paying. Brown cards make raw materials, grey cards make manufactured goods, and your wonder board makes one resource from the start. What you produce, you spend for free. What you lack you can buy from either neighbour — 2 coins per resource, and they don't lose the resource by selling it. Trading posts and the Marketplace bring that down to 1.
Chains. Some cards name a building on their left edge: if you already have it, the new card is free, no matter what it costs. You may never build two cards with the same name.
Military. Red cards give shields. At the end of every Age you compare shields with each neighbour separately: more shields wins a token worth 1, 3 or 5 by Age, fewer loses one worth −1. Equal, nothing happens.
Science. Green cards show a compass, a gear or a tablet. At the end you score the square of how many you have of each symbol, plus 7 for every complete set of all three. Two of each is 26; three of each is 48.
Everything else: blue cards are flat points, yellow cards make money or score off what you have built, purple guilds mostly score off what your neighbours have built, and every 3 coins left at the end is worth 1 point.
Leaders (if the room has them on). Before Age I you are dealt four white leader cards and draft four: keep one, pass the rest to your right, repeat. Then at the start of every Age, before the cards are dealt, everyone plays one leader at the same time — recruit it by paying the coins in its corner, bury it under your wonder to build a stage, or sell it for 3. A few leaders cost "the Age": 1 coin in Age I, 3 in Age III. Three Ages against four leaders, so one of yours never gets played. Everyone starts with 6 coins instead of 3, because leaders have to be paid for out of the same purse the first Age does.
Most points wins; ties go to whoever has the most coins.
Cards, guilds and wonder boards follow the second edition (2020). If you learned the game on the first, a few things moved: the Pawnshop is now the Well and chains into the Statue, the Altar chains straight to the Pantheon, the Strategists Guild has become the Decorators, and most of the wonder boards were re-costed.