Common Shores
Specialize and trade. Build a self-sufficient city. Discover what you can achieve together—or at each other’s expense.
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My Account / unlock adult settingsIsland preview. Host or join to make decisions with other players.
An island of possibilities
Select land to inspect, expand, or build.
Colored borders show city territory. Trade routes appear after accepted trades. A growing capital reflects its population.
CHOOSE YOUR PATH
City specialization
Free in the lobby. Changes cost 1 action during a match. Specialists can trade their surplus; self-sufficient cities receive broad production bonuses.
NEXT SEASON’S OUTLOOK
Production & food needs
Gather supplies · 1 action
Timber and stone gathering each lower ecology by 1. Food feeds one person per unit each season. Extra homes raise the population cap.
PLAYER-TO-PLAYER MARKET
Offer your surplus
Your offered resources are reserved. Acceptance costs the other city 1 action. Unaccepted offers return their supplies after two season changes; you may cancel before ending your season. Maximum three open offers per city.
DIPLOMACY
Your island neighbors
Mutual peace lasts three season changes and blocks territorial contests between the two cities. Proposing and accepting peace use no actions. Breaking it costs 1 action and 15 island trust.
BUILD SOMETHING BIGGER
Projects for the whole island
Contributions cost 1 action. Every completed project benefits every city, regardless of who funded it.
THE WORLD YOU CREATED
Your choices leave a record
Season history: Ecology · Trust · Average wellbeing. These are the observed results of this match.
| City | Approach | People | Wellbeing | Trades | Shared supplies | Score |
|---|
How city scores work
Population × 4 + non-capital buildings × 3 + half wellbeing + traded units ÷ 4 + shared project supplies ÷ 4 + owned tiles + coin ÷ 5. Fractional score components round down except wellbeing, which rounds to the nearest point. Both sides earn commerce credit for a completed trade.
Island timeline
Build your civilization, choose your relationships
Each season gives every city 3 actions. Build and expand, gather supplies, trade, or fund infrastructure. End your season when ready; production resolves when everyone finishes or the clock runs out. Food shortages reduce population and wellbeing. Forecasts show your expected food balance before you commit.
There are two results: the highest-scoring city, and the island’s shared prosperity. Shared prosperity requires ecology of at least 60, every city’s wellbeing of at least 55, and two completed shared projects. Personal success can coexist with a thriving island—or leave you leading a struggling one.
Territorial contests cost 6 timber, 8 coin, 6 food and 2 actions. Attack is 4 + 2 per watchtower + population ÷ 8 rounded down. Defense is 4 + 2 per watchtower, plus 2 next to a capital. A contest succeeds only when attack exceeds defense. Every contest costs both cities 3 wellbeing and the island 12 trust and 2 ecology. Capitals cannot be captured.
This is a simplified strategy simulation, not a real-world economic forecast. Anyone can join with a room code. A verified adult account with adult settings unlocked is required to host. Leaving a match makes your city pass future decisions; its economy and history remain on the island. There is no reconnect or saved match, and access lasts up to one hour per connection.