New riders designing virtual worlds

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Designing Virtual Worlds
By Richard A. Bartle

Publisher: New Riders Publishing
Pub Date: July 14, 2003
ISBN: 0-1310-1816-7

Copyright
Acknowledgments
About the Author
About the Technical Reviewers
Tell Us What You Think
Preface
Introduction
Who Should Read This Book?
Overview
Chapter 1. Introduction to Virtual Worlds
Some Definitions
What They Are and Whence They Came
The Past Affects the Future
The Basics
Influences on Virtual Worlds
The Designer
Chapter 2. How to Make Virtual Worlds
Development
On Architecture
Theory and Practice
Chapter 3. Players
Who Are These People and What Do They Want?

Player Types
Other Categorizations
The Celebration of Identity
Anonymity
Role-Playing
Masquerading
Community
Influence Through Design
Chapter 4. World Design
Scope
Major Decisions
Geography
Population
Physics
Reset Strategy
Chapter 5. Life in the Virtual World
Advancement


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Character Generation
The Virtual Body
Groups
Combat
Crafting
The Elder Game
The Whole Picture
Chapter 6. It's Not a Game, It's a.
Points of View

Making Sense of Virtual Worlds
Virtual Worlds as Subfields
Virtual Worlds as Tools
Virtual Worlds as.Virtual Worlds
Conclusion
Chapter 7. Towards a Critical Aesthetic
A Theory of Virtual Worlds
The Story of Story
The Critical Aesthetic in Use
Chapter 8. Coda: Ethical Considerations
Censorship
Players as People
Groups of Players as Groups of People
Yourself

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Copyright
Copyright © 2004 by New Riders Publishing
All rights reserved. No part of this book shall be reproduced, stored in a retrieval
system, or transmitted by any means— electronic, mechanical, photocopying,
recording, or otherwise—without written permission from the publisher, except for the
inclusion of brief quotations in a review.
Library of Congress Catalog Card Number: 2003106801
Printed in the United States of America
First printing: July, 2003
08 07 06 05 04 03 7 6 5 4 3 2 1

Interpretation of the printing code: The rightmost double-digit number is the year of the
book's printing; the rightmost single-digit number is the number of the book's printing.
For example, the printing code 03-1 shows that the first printing of the book occurred
in 2003.

Trademarks
All terms mentioned in this book that are known to be trademarks or service marks
have been appropriately capitalized. New Riders Publishing cannot attest to the
accuracy of this information. Use of a term in this book should not be regarded as
affecting the validity of any trademark or service mark.

Warning and Disclaimer
Every effort has been made to make this book as complete and as accurate as
possible, but no warranty of fitness is implied. The information is provided on an as-is


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basis. The authors and New Riders Publishing shall have neither liability nor
responsibility to any person or entity with respect to any loss or damages arising from
the information contained in this book or from the use of the CD or programs that may
accompany it.

Credits
Publisher
Stephanie Wall
Production Manager
Gina Kanouse
Acquisitions/Development Editor
Chris Zahn

Project Editor
Michael Thurston
Copy Editor
Linda Seifert
Indexer
Julie Bess
Proofreader
Debbie Williams
Composition
Gloria Schurick
Manufacturing Coordinator


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Dan Uhrig
Interior Designer
Kim Scott
Cover Designer
Aren Howell
Marketing
Scott Cowlin
Tammy Detrich
Hannah Onstad Latham
Publicity
Susan Nixon

Dedication
To the players.

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Acknowledgments
This book would not have been written were it not for:
John Neidhart at Pearson Education, who was willing to indulge my desire to write
about virtual world design despite the fact that he was actually looking for a book
about AI.
Stephanie Wall and Chris Zahn at New Riders, who gave me an enthusiastic welcome
when I appeared on their doorstep at short notice as a result of a Pearson
reorganization. They gave me the time and freedom I needed to finish the job
properly.
My wife, Gail Bartle. From June 2002 until April 2003, I turned down all consultant and
design work I was offered so I could write this book. Without her quiet but unfailing
support, you wouldn't be reading this now.
I'd also like to thank Damion Schubert and Matt Mihaly for the many insightful
comments they made in their reviews (sometimes several to a page). This book would
still have been written without them, it just wouldn't have been as worth reading.

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About the Author
Richard Allan Bartle, Ph.D., co-wrote the first
virtual world, MUD ("Multi-User Dungeon"), in
1978, thus being at the forefront of the online
gaming industry from its very inception. A former

university lecturer in Artificial Intelligence, he is
an influential writer on all aspects of virtual world
design and development. As an independent
consultant, he has worked with almost every
major online gaming company in the U.K. and
the U.S. over the past 20 years.
Richard lives with his wife, Gail, and their two children, Jennifer and Madeleine, in a
village just outside Colchester, England. He works in virtual worlds.

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About the Technical Reviewers
These reviewers contributed their considerable hands-on expertise to the
development process for Designing Virtual Worlds. As the book was being written,
these dedicated professionals reviewed all the material for technical content,
organization, and flow. Their feedback was critical to ensuring that Designing Virtual
Worlds fits our readers' need for the highest-quality technical information.
Matt Mihaly is the founding partner, lead
designer, and CEO of Achaea LLC. Founded in
1996 in San Francisco, Achaea designs and
produces some of the world's most popular and
successful commercial text MUDs, including
Achaea, Dreams of Divine Lands
(), Aetolia, the Midnight
Age (), and Imperian
()—all of which run on
Achaea's proprietary network engine, Rapture.

Matt graduated from Cornell University in 1994 with a degree in Political Science and
is a licensed stockbroker. These experiences have informed his game design
tendencies and he is an expert on business models, political systems, and community
dynamics in virtual worlds. Along with the inevitable interest in games, he spends his
free time pursuing Brazilian jujitsu and kickboxing, cooking, travelling, hiking,
kayaking, skiing, and scuba diving.
Damion Schubert has been working in online
world design professionally for over seven
years. He was originally the lead designer of
Meridian 59 (and several expansions), as well as
the lead designer for the defunct Ultima Online
2. He has also served as a contractor for such


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projects as The Sims Online and Kalisto's
Highlander Online. Currently Damion is serving
as a senior designer at Wolfpack, which shipped
Shadowbane in March 2003.

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Tell Us What You Think
As the reader of this book, you are the most important critic and commentator. We
value your opinion and want to know what we're doing right, what we could do better,
what areas you'd like to see us publish in, and any other words of wisdom you're
willing to pass our way.

As the Publisher for New Riders Publishing, I welcome your comments. You can fax,
email, or write me directly to let me know what you did or didn't like about this
book—as well as what we can do to make our books stronger. When you write, please
be sure to include this book's title, ISBN, and author, as well as your name and phone
or fax number. I will carefully review your comments and share them with the author
and editors who worked on the book.
Please note that I cannot help you with technical problems related to the topic of this
book, and that due to the high volume of email I receive, I might not be able to reply to
every message.
Fax:

317-581-4663

Email:



Mail:

Stephanie Wall
Publisher
New Riders Publishing
rd

201 West 103 Street
Indianapolis, IN 46290 USA

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Preface
The aim of this book is to make people think about virtual world design. Whether you
agree with any of it is not an issue, as long as you advance your own thoughts on the
subject.
Too much virtual world design is derivative. Designers take one or more existing
systems as foundations on which to build, sparing little thought as to why these earlier
worlds were constructed the way they were. This is troubling, not because it leads to
artistic sterility—designers are always imaginative enough to make their creations
special—but because the resulting virtual worlds might not work as well as they could.
If designers don't know the reasoning behind earlier decisions, how can they be sure
that the conditions that sustained those decisions still apply when they act on them?
Are designers even aware that there are decisions they can unmake?
Although a good deal of design is evolutionary, that does not mean designers can't be
revolutionary too. Virtual worlds are all about freedom—for their inhabitants, yes, but
also for their designers. Just because every virtual world you can think of classifies
characters using some variation of a basic four-profession model, that doesn't mean
your virtual world has to classify them that way; more to the point, it doesn't even
mean that your virtual world has to classify characters at all.
Virtual worlds are unlike anything else. You can't approach them from a background in
some other area—game design, literature, media studies, architecture, or
whatever—and expect all the normal rules to apply. Unfortunately, it doesn't look that
way from the outside. "How hard can it be?" is a question often asked by people
entering the field from some related area that is considered to be Pretty Damned
Tough.
Then they find out.
If they're lucky, they find out quickly. If they're unlucky, they only find out after 18

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months and half their budget. Designing virtual worlds is very difficult, unless you know
what you're doing; then, it's no harder than any other complex design activity.
The key is in recognizing the fact that what seems eminently logical to you from your
usual perspective might turn out to be disastrous when viewed from another
angle—and then realizing that the worlds you're drawing inspiration from almost
certainly contain elements designed by people who didn't recognize that fact until it
was too late.
To design a virtual world is perhaps the greatest act of creative imagination there can
be. The possibilities are absolutely limitless—you can make and do anything in them.
Anything! Today's virtual worlds are mere children's scribbles compared to the
masterpieces to come.
We see these scribbles, but have no concept of how the masterpieces will appear; the
virtual worlds of the future will not be like the virtual worlds of today, in ways we
cannot yet know. Thus, much of what you read in this book is doomed, eventually, to
be proven wrong. However, it might well point the way to discovering what is right. All
it takes is for people to think about what they're designing; if reading this book helps in
that respect, then it has done its job.
I don't care what you think, so long as you think.

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Introduction
Every day, over a million people visit virtual worlds—a figure set to grow over the
coming years. What is it that draws them to these imaginary places? What do they do
after they've arrived? How can the people who create such worlds—their
designers—ensure that players' needs are met? Can they do this while satisfying their

own needs, too?

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Who Should Read This Book?
This is a book for people who design virtual worlds.
Because of this, it's also a book for people who implement, operate, study, or play
virtual worlds.
Because of this, it's also a book for people interested in entertainment, education,
creativity, art, society, culture, philosophy, space, architecture, psychology, identity,
language, economics, government, theology, drama, literature, or cognition.
Virtual worlds are of the future. If you want to create or understand that future, this is
the book for you.

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Overview
The material presented here is organized such that it begins with concrete facts and
moves gradually toward abstract conjecture. As it does so, theories of virtual world
play and creation are developed that ultimately demonstrate the validity of virtual
world design as an object of study.

Chapter 1: Introduction to Virtual Worlds
What are virtual worlds? Beginning with an historical account of how they came to be

where they are today, this chapter moves on to describe the various categories of
virtual worlds that exist and what these categories mean for designers. Influences
from other art forms are presented to explain some directions virtual world design has
taken.

Chapter 2: How to Make Virtual Worlds
This is a relatively short chapter that outlines the development process commonly
employed for virtual worlds and the effects this process has on what designers can
do. It includes an examination of how virtual worlds are typically implemented and the
constraints this implies.

Chapter 3: Players
This major chapter concerns the people who play virtual worlds. Only by fully
understanding why people play can designers hope to accommodate these players'


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needs. It focuses on two important concepts, immersion and identity, and how they
can be related using an enhanced "player types" model. It follows with a discussion
about community in virtual worlds, and how it fits in with all this.

Chapter 4: World Design
Here, the practical decisions designers must make concerning the creation of virtual
worlds are described, with reference to the theory developed in Chapter 3. The
various options available at each stage are presented, with explanations as to why
designers may or may not want to incorporate them into their creations.

Chapter 5: Life in the Virtual World
In this chapter, the spotlight falls on characters, rather than the players behind them.
Various ways to represent character skill, experience, and advancement are

discussed, along with different systems for allowing characters to form groups.
Combat and crafting activities are described, as are the various "endgames" to which
they can lead. The theory of Chapter 3 is mainly used in application here, but it does
receive a final extension that makes clear exactly why players do play virtual worlds.

Chapter 6: It's Not a Game, It's a…
This is an academic chapter that shows the design of virtual worlds to be a serious
topic of research. By studying what other fields find interesting in virtual worlds, the
boundaries of the subject can be ascertained and its worth assessed. Also, insights
from research by experts from other disciplines can be picked up by designers and
applied directly. The aim of this chapter is credibility: Virtual worlds are not "just a
game," they're something entirely new.


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Chapter 7: Toward a Critical Aesthetic
This is another credibility exercise, although in this case it's to defend virtual world
designers from their critics within the arena of virtual worlds rather than their critics not
involved in virtual worlds. The purpose of this chapter is to justify this statement:
Virtual world design is an art form. To do this, it develops a critical aesthetic—a way of
extracting meaning from designers' work that frees them to innovate further.

Chapter 8: Coda: Ethical Considerations
This final chapter discusses the morals of virtual world design. It asks plenty of
questions, but doesn't provide many answers; the idea is to alert designers to their
responsibilities, rather than lecture them about how they should behave.

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Chapter 1. Introduction to Virtual Worlds
KEY TOPICS
Some Definitions
What They Are and Whence They Came
The Past Affects the Future
The Basics
Influences on Virtual Worlds
The Designer
What are virtual worlds? In this context, a world is an environment that its inhabitants
regard as being self-contained. It doesn't have to mean an entire planet: It's used in
the same sense as "the Roman world" or "the world of high finance."
So what about the virtual part? Not to get too philosophical about it:
Real. That which is.
Imaginary. That which isn't.
Virtual. That which isn't, having the form or effect of that which is.
Virtual worlds are places where the imaginary meets the real.

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Some Definitions
Virtual worlds are implemented by a computer (or network of computers) that
simulates an environment. Some—but not all—the entities in this environment act
under the direct control of individual people. Because several such people can affect
the same environment simultaneously, the world is said to be shared or multi-user.
The environment continues to exist and develop internally (at least to some degree)

even when there are no people interacting with it; this means it is persistent.
Although virtual worlds now have many applications beyond that of being mere
entertainment products, they began as computer games; furthermore—perhaps
because of the large sums of money involved in their creation and the guaranteed
huge monthly incomes they can generate—computer games remain at the cutting
edge of virtual world development.
For these reasons, much of the vocabulary commonly used to describe virtual worlds
is games-based. Thus, the human beings who interact with the simulated environment
are known as players rather than users; the means by which the environment
introduces goals for the players is called gameplay; the activity of interacting with the
environment is referred to as playing.
Specialists may adopt a different vocabulary that is formal for their particular area of
expertise, for example a cultural anthropologist might prefer to talk of "individuals"
exhibiting "behaviors" in response to "pressures;" however, for any broader discussion
of the subject the dominance of game-oriented terminology is impossible to resist, and
it is therefore the one that shall be used here.
The exception is the very term "virtual world" itself. Over the years, a number of
words, phrases, and contrived acronyms have been used to describe these projected
milieux, none of which have been entirely successful. For reasons that will be
explained shortly, virtual worlds were originally known as MUDs (Multi-User
Dungeons) .


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Although this term is still in common currency to the extent that it has made it into
several regular dictionaries, it is not universally accepted. In particular, many players
of certain of its subcategories see it as implying some kind of combat-oriented world
view, and prefer the term MU* instead (MU for Multi-User and * for anything that
could conceivably follow).

This would be analogous to calling dinosaurs *saurs on the grounds that "dinosaurs"
[1]

vaguely implies

that they were all pea-brained carnivorous monsters, whereas in fact

many were pea-brained herbivorous monsters—and hey, there are pterosaurs and
plesiosaurs, too.
[1]

"Dino" comes via New Latin from the Greek deinos, meaning

"fearful." Saurus merely means "lizard."
The first virtual worlds were text-based, in that their environments and the events
occurring within them were described using words rather than images. Confusingly,
although the term MUD applies to virtual worlds in general, the term MU* does
not—it's used strictly for text-based worlds. The introduction of computer graphics into
the mix therefore caused a second spate of naming, in order to make a distinction
between graphical MUDs and text MUDs . At first the new games were called
persistent worlds , but when the enormous numbers of simultaneous players they
were attracting became their defining feature this changed to MMORPGs
(Massively-Multiplayer Online Role-Playing Games) . Said acronym dominates at
present, but it is rarely used with enthusiasm (not least because it's unpronounceable)
and it is therefore likely to be abandoned the instant some viable alternative emerges.
Although, properly, all these persistent, shared, computer-moderated environments
can and should be referred to as MUDs, the term is sufficiently loaded that outside the
cognoscenti it is unlikely to be universally interpreted this way. Enough people think
that MUDs are a mere category of MU*s (rather than the reverse) for it to be
confusing. Therefore, this book prefers the more descriptive and less emotive "virtual

worlds" as an alternative.
It is important to note that virtual worlds are not the same as virtual reality (VR) ,
which has a much more specific meaning. Virtual reality is primarily concerned with
the mechanisms by which human beings can interact with computer simulations; it is
not especially bothered by the nature of the simulations themselves. People who visit


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virtual worlds may some day benefit from research into visors, data gloves, and
beyond, but the fundamental attraction for them is what awaits when they enter a
virtual world, not the means by which they do so.

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What They Are and Whence They Came
Although more abstract versions can, and do, exist, most virtual worlds adhere to
certain conventions that distinguish them from related non-real spaces. The most
important of these are
The world has underlying, automated rules that enable players to effect
changes to it (although not to the rules that grant them this ability). This is the
world's physics.
Players represent individuals "in" the world. They may wield partial or total
influence over an army, crew or party, but there is only one game entity that
represents them in the world and with which they strongly identify. This is their
character. All interaction with the world and other players is channeled through
characters.
Interaction with the world takes place in real time. When you do something in

the world, you can expect feedback almost immediately.
The world is shared.
The world is (at least to some degree) persistent.
A chat room would not be a virtual world because it has no physics; a strategic
wargame doesn't map the player onto a single character through which that player
acts; a play-by-email game doesn't run in real time; a single-player game is not
shared; a first-person shooter isn't persistent.
For some examples, the case is not so clear-cut. Are tabletop role-playing games
virtual worlds, for example? No, because they're not automated, but it's a close call.
Would a two-player educational MUD be a virtual world? Probably. Would a
500-player game with a world so vast that the players could never find each other?
Yes, but under protest.


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In practice, it's fairly easy to determine what is or isn't a virtual world simply by looking
at its heritage. If its design draws heavily from the design of an existing virtual world, it
almost certainly is one; if it doesn't, it almost certainly isn't.

The First Age: 1978–1985
Virtual worlds are often called MUDs because MUD was the name of the first one to
prosper. Although earlier games had been written that might today be described as
virtual worlds, they were seeds that fell on stony ground. MUD, by contrast, grew to
produce seeds of its own.
MUD was programmed in MACRO-10 assembler on a DecSystem-10 mainframe at
Essex University, England, in the fall of 1978. Its author was a talented Computer
Science undergraduate, Roy Trubshaw. Version I was a simple test program to
establish the basic principles by which a shared world could be maintained. When it
worked, Roy immediately started on version II, a text-based virtual world that would be

instantly recognizable as such even today. It was also written in MACRO-10, a
decision that led to its becoming increasingly unwieldy as more and more features
were added. Because of this, in the fall of 1979 Roy made the decision to begin work
on version III of the game. He split it in two: The game engine was written in BCPL
(the fore-runner of C); the game world was written in a language of his own devising,
MUDDL (Multi-User Dungeon Definition Language) . The idea was that multiple
worlds could be constructed in MUDDL but would run on the same, unmodified engine
(which was effectively an interpreter).
Roy had a basic working program by Easter 1980, but it only amounted to a fraction of
what he envisaged. This being the final year of his degree, he realized that he did not
have time to complete the project. Someone else would have to do it.
From the beginning, Roy had been open to suggestions from his friends as to how
MUD could be extended and improved. Most of these ideas came from fellow
undergraduates Richard Bartle (that's me) and Nigel Roberts. Unlike Nigel, I was
younger than Roy and did not have to leave the university for another year (in fact, I
was to stay until 1989; first as a postgraduate and then as a lecturer). Luckily, I was
also a first-class programmer and had a strong background in gaming. Roy therefore


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passed MUD on to me, and I subsequently wrote the remainder of the engine and
nearly all the world to produce what became the paradigm for the entire genre. That's
enough blowing my own trumpet, you'll be relieved to know.
Roy had two motivations to write MUD. First, he had enjoyed single-player adventure
games (Crowther and Woods' ADVENT ; Anderson, Blank, Daniels, and Lebling's
ZORK ; Laird's HAUNT ) and liked the idea of creating a multiplayer game along those
lines. Secondly, he had a strong academic interest in writing programming language
parsers and interpreters. The two came together when he discovered a means of
sharing write-enabled areas of memory on the DEC-10 mainframe and mused on its

potential uses.
The "D" in MUD stands for "Dungeon." Contrary to what many people assume, this
has nothing to do with the role-playing game Dungeons & Dragons and does not
[2]

mean that the game world had a dungeon setting . Instead, it is due to the fact that
the version of ZORK Roy played was a Fortran port called DUNGEN

[3]

. Roy wanted

something that was like a multi-user DUNGE(o)N, and the acronym MUD immediately
presented itself.
[2]

[3]

This is just as well, as it didn't.
The DEC-10 used six-character, all uppercase filenames. This is why

"Dungeon" is referred to as DUNGEN and "Adventure" as ADVENT by
old-time hackers like me.
Essex University is a mere 45 minutes by road from the main (what was then the Post
Office, but is now) British Telecom research facility, located at Martlesham Heath near
Ipswich. This caused the university to be selected to pilot a new, experimental
packet-switching service called EPSS. Among other things, EPSS allowed contact to
and from the ARPA (Advanced Research Project Agency) net in the United States.
Roy could therefore tell people in the U.S. about MUD, and some of them came to try
[4]

it out . The ARPA net eventually evolved to become what is known today as the
Internet.
[4]

A fact that has busted more than one twisted patent claim.

Nevertheless, MUD remained a mainly Essex University phenomenon in its


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formative years, existing primarily because of the largesse of the Computer Services
team and their manager, Charles Bowman . In the teeth of complaints about wasted
resources, members of the university's Computer Society were allowed to spend
off-peak time doing anything non-academic they liked. Many of them chose to play
MUD.
Some, however, were inspired to write their own games in MUDDL for use with the
MUD engine. There were a number of these, of which the pre-eminent were ROCK
(based on TV's Fraggle Rock Muppet show), MIST (original and anarchic), BLUD
(original and bloody), and UNI (the Computer Science Department as a
sword-and-sorcery virtual world).
Besides its EPSS connections, Essex University also had a number of modems for
dial-up use. News of MUD reached the U.K.'s small community of BBS (bulletin board
system) users, and they obtained permission to play the game by direct dial—just as
long as they did so at times when any sane person would have been in bed for two
hours. This they did, and demand grew so much that that they clubbed together and
bought the university some extra modems so it could cope…!
Network uptake increased, and eventually all U.K. universities were connected to a
system called JANet (Joint Academic Network) . EPSS ceased to be experimental

and became PSS, which enabled people with access to either company PSS
accounts or substantial amounts of money to connect to the university's computer
systems in yet greater numbers. In 1984–85, there were articles on MUD in practically
all the specialist computer games magazines in the U.K. The floodgates opened.
[5]

The MUD engine had its limits. It could hold a maximum of 36 players at once , and if
more wanted to play then a second game would have to be cranked up to supersede
the first. Furthermore, it only ran on a DEC-10, and although copies were sent to other
institutions in the U.K., Sweden, and Norway, only two of these allowed outsiders
access (Dundee Technical College and Oslo University).
[5]

The DEC-10 used a 36-bit world, and Roy assigned 1 bit per player

for internal reference.
While Roy was still working on version II of MUD, another student at Essex University,
Stephen Murrell , had written from scratch his own virtual world using a different
means of handling inter-player communication (that of assigning devices). His game,