one dataset · paper, tables, graph, wiki
simgrammar the grammar of simulation

parts

15 mechanics, as Eco does them

core · 4

time & pacing

Crisis countdown

A meteor is set to strike in thirty days, and players must gather resources and research technology to stop it without harming the world.

environment & ecology

Food web

Thousands of plants and animals from dozens of species grow across the world; overhunting or overharvesting can drive a species extinct, and a disruption in one species cascades across the planet.

governance & policy

Player legislation

Players propose laws in a programmable rule system and vote on them, the game enforces ratified laws, and elections set tax rates and community funds; governments range from dictatorships to lawless, trust-based communities.

environment & ecology

Pollution spread

Mining waste and industrial pollution poison rivers and kill farms, and excessive air pollution raises sea levels.

supporting · 11

agents & behavior

Agent skills

Varied food and larger homes earn skill points spent on specialties such as farming, hunting, trade, and engineering.

economy & finance

Contracts and orders

Players post labor contracts for others to fulfill.

governance & policy

Elections

multiplayer & persistence

Modding API

The official modkit lets servers add C# items, recipes, and rules.

environment & ecology

Planetary climate

Accumulated pollution changes the climate and sea level.

economy & finance

Player-driven markets

Players run stores and currency exchanges with fiat or resource-backed currencies and set exchange rates.

resources & production

Production chains

More than 30 craft tables turn materials into goods across hundreds of recipes.

resources & production

Renewable regrowth

Plant and animal populations recover over time unless harvested faster than they regrow; cutting too many trees reduces how much air pollution is absorbed.

multiplayer & persistence

Seasonal world reset

Each world is bounded by a meteor due in thirty days, so a server's run ends with stopping it or with impact, and servers are commonly wiped and restarted as fresh worlds.

economy & finance

Taxation

progression & goals

Tech tree

core loop

gather from the shared ecosystem -> specialize in skills and craft at tables -> trade through player stores and currencies -> propose and vote on laws and taxes -> research technology to stop the meteor -> manage pollution and species populations before impact

design notes

Eco makes the ecosystem a shared commons: each player's harvesting and pollution changes species populations and the climate for everyone on the server. Its answer to overexploitation is player-made institutions rather than designer rules, with enforceable laws, taxes, and currencies, and simulation data that players can cite as evidence in debates. It began as an educational project funded in part by the U.S. Department of Education.

appears in

the paper, 3 sections · 2 chapters
paper

4. A grammar of simulation games

linked in this section of the paper

paper
paper

5. The structure of the design space

linked in this section of the paper

paper
paper

Appendix A. Game catalog

linked in this section of the paper

paper
catalog

The catalog

listed with its year, developer, subgenre, and number of mechanics

book
ch 4

Chapter 4. Families

linked from the text

book
ch 10

Chapter 10. Bets

linked from the text

book

sources

2
Wikipedia contributors (2026). Eco (2018 video game). Wikipedia
(2026). Eco on Steam. Steam

provenance

runs in log/runs
2026-10-24
created2026-10-24-catalog-gicatalog
2026-10-25
reviewed2026-10-25-contributor-readinessmaintenance