18XX: A System of Systems
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Prior to COVID I had a fairly regular game group that focused almost<br>entirely on playing economic train games known as “18XX”.1<br>There is no single game called “18XX” and the term is used to describe a<br>family of games that generally involve participating in and manipulating<br>a stock market, managing a portfolio, building train networks, and<br>guiding the operations of train companies. The 18XX family began in 1974<br>with Francis<br>Tresham’s 1829, a<br>pioneering design that was followed up 12-years later by the cutthroat<br>1830:<br>The Game of Railroads and Robber Barons.2 In<br>the decades since, dozens of designers have created hundreds of variants<br>and expansions and even today there are still publishers releasing new<br>18XX games. Why has this niche family spawned so many titles over nearly<br>five decades? The reason is that the underlying 18XX framework is a<br>modular, interlocking system that leaves vast room for innovation in its<br>levers, constraints, and feedback loops. In this post I’ll talk about<br>the 18XX subsystems and briefly how they interact, with a couple of<br>brief sidelines into specifics, to try and paint a picture about the<br>robustness of the common mechanics.
Some of Tresham’s 18XX games
Each Game is Three Sub-games
Every 18XX balances to varying degrees three sub-games:
A stock market game - buy, sell, and manipulate shares
A network game - lay track, connect cities, run trains
A technology race - buy, upgrade, and obsolete trains (and<br>other game-specific techs)
These are three loosely coupled modules with tight feedback loops.<br>Output from one is input to the others and back again.
The progression of 18XX games is clocked by alternating phases:
Operating Rounds (OR) - when players, on behalf of their<br>companies, build or upgrade track or stations, buy or sell trains, and<br>run trains on the tracks for (hopefully) profit, and choose to pay or<br>withhold dividends to stockholders
Stock Rounds (SR) - when players buy or sell shares in<br>companies, and float new companies
While the general flavor of most 18XX ORs and SRs are the same,<br>there’s a<br>lot of room for nuance that each game in the family utilizes in<br>unique ways. For example, there are often limits on dumping stock, but<br>1830 eschews limits allowing the president of a train company to empty<br>its coffers, sell its trains, and then dump stock, assigning one of the<br>minority shareholders as the new president and on the hook for covering<br>all mandatory costs.
Sub-games as Feedback Loops
One of the genre’s most interesting properties is how the sub-games<br>feed each other.
Network –> Stock: Build a great route, run a profitable<br>train, your company’s share price rises
Stock –> Technology: Force a rival to buy an expensive<br>train early, their treasury empties, delaying track upgrades and<br>stations
Technology –> Network: Permanent trains enable long<br>routes, making certain tiles, stations, and connections more<br>valuable
Harzbahn 1873 tracks and<br>mines
In any game, players can interact with and intervene in this feedback<br>loop to influence the thrust of the game. Often these interventions are<br>intractable in their long-term effects, which adds uncertainty into a<br>system that is usually open to complete observation.
High Information, Butterfly<br>Effects
In general, the information available to 18XX players within a game<br>is open for all to see and reason about. Players can see the map, the<br>stock prices, the train roster, (usually) other players’ holdings, and<br>random effects are very rare once games have started. For the most part,<br>18XX games are calculable given the information available to all of the<br>players.
In practice however, small nudges in one element of an 18XX can cause<br>rippling, “butterfly<br>effects.” A few examples are:
A missing tile in the manifest, or a blocking station token can<br>force costly detours or shut out players from map regions
A price token pinned to a ledge on the stock chart can blunt the<br>rise or fall of that stock’s value
Careless par price selection can ripple effects throughout the<br>course of an entire game
The priority deal that (defining who gets first action in a SR) can<br>motivate company gutting and stock-dumping
Train “rusting” usually triggers when certain newer model comes into<br>play, wiping old models out of the game, flipping a company from one<br>that reaps healthy revenue to an insolvent one
The examples above are only a few examples of the kinds of knobs that<br>18XX designers play with, making 18XX games fun laboratories for<br>studying deterministic chaos. While the rules of any given game are<br>fixed, emergent behavior and butterfly effects beget depth of<br>possibility and play.
Four Strategic Archetypes
Across its many variants, 18XX offers four<br>broad games inside the game:3
Run Good Companies - shepherd one or two firms from humble<br>beginnings to efficient networks, permanent trains, and stable<br>dividends
Find the Free Money - dividends from others’...