Games & Virtual Worlds Series

Systems Concepts

Understanding Games: How Video Games & Board Games Work

Michael Filimowicz, PhD

Published in

Understanding Games

12 min readJan 3, 2023

Games as Systems of Systems

A game system is a player-organized or designer-created collection of game mechanics which can be understood mostly in isolation from other systems and that controls a significant group of related, nontrivial behaviors of gameplay toward a specific outcome….Systems are a collection of mechanics which give rise to dynamics connected to a specific area of gameplay.
— Brenda Romero

We’ve already provided a high-level overview of the significant historical moments that led to the creation of digital (i.e. computer-based) games; now, let’s dive deeper into the digital realm of games (though not in the same way as done in the Tron movies :) by focusing on the systems that make up a video game.

The term ‘system of systems’ can be used to describe or examine most advanced technical objects. That is to say, the whole thing — here, a digital video game — could be viewed as a system that consists of multiple subsystems. This is analogous to how a human body is thought to be organized into many systems like the circulatory, endocrine, neurological, digestive, and so on. For the sake of clarity, let’s start with a few definitions.

System:

A system is a collection of elements or components that are organized for a common purpose. The word sometimes describes the organization or plan itself (and is similar in meaning to method, as in “I have my own little system”) and sometimes describes the parts in the system (as in “computer system”).
A computer system consists of hardware components that have been carefully chosen so that they work well together and software components or programs that run in the computer.
The main software component is itself an operating system that manages and provides services to other programs that can be run in the computer. A filing system is a group of files organized with a plan (for example, alphabetical by customer).
All of nature and the universe can be said to be a system. We’ve coined a word, ecosystem, for the systems on Earth that affect life systems. The term can be very useful because so many things can be described as systems. It can also be very unuseful when a more specific term is needed.
— “system of systems (SoS), techtarget.com)

System of Systems:

A system of systems (SoS) is the collection of multiple, independent systems in context as part of a larger, more complex system. A system is a group of interacting, interrelated and interdependent components that form a complex and unified whole.
These independent and possibly distributed systems pool their resources together, creating a new and more complex system. Individual systems in an SoS work together to provide functionalities and performance that none of the independent systems, or constituent systems, could accomplish on their own.
The goal of an SoS architecture is to get maximum value out of a large system by understanding how each of the smaller systems works, interfaces and is used. Such system designs require systems thinking — a holistic approach to analysis that focuses on the way constituent parts interoperate, work over time and function within the context of a larger, evolving system.
— “system of systems,” techtarget.com)

The very definition of a system implies the presence of several interdependent pieces that work together to achieve a common goal. The systems of a game are the mechanisms through which the player’s inputs are processed and the intended outcomes are realized.

Non-triviality is also an important contributing parameter, as many potential events in a video game may not have their own specific system. A game mechanic is a specific rule or system within a game that determines how the game functions and is played. Game subsystems are larger, more complex systems that are made up of multiple game mechanics and may have their own set of rules and procedures.

Whether or not a game mechanic requires its own specific game subsystem depends on several factors. One factor to consider is the complexity of the mechanic. If a game mechanic is simple and self-contained, it may not need its own subsystem. However, if the mechanic is more complex and involves multiple steps or interactions with other mechanics, it may be more efficient to create a subsystem to manage it.

Another factor to consider is the importance of the mechanic to the overall game. If the mechanic is a core part of the game and is used frequently, it may make sense to create a subsystem to manage it. On the other hand, if the mechanic is only used occasionally or is less integral to the game, it may not be necessary to create a separate subsystem.

Ultimately, the decision to create a specific subsystem for a game mechanic will depend on the needs and goals of the game design.

A game system needs to play a significant part in the game as a whole before it can be considered independent in terms of its information architecture (i.e., programming and its relationship to other game systems). However, it is possible that opening doors is crucial to the gameplay, in which case you should have a door system if there are many ways to open doors, such as by kicking them in, shooting a gun at them, using biometrics, or even just a plain ol’ boring key.

The overall game design determines whether a certain aspect of the game is trivial or nontrivial.

Even something as seemingly straightforward as a doorway can become entangled in the web of design considerations and technical details. When creating a game’s stages, game designer Liz England (“Video Games and the Door Problem,” kotaku.com, 2016) suggests asking the following “door questions”:

Can the player open them?

Can the player open every door in the game?

Or are there some doors for decoration?

How does the player know the difference?

Are doors you can open green and ones you can’t open red? Is there trash piled up in front of doors you can’t use? Did you just remove the doorknobs and call it a day?

Can doors be locked and unlocked?

What tells a player a door is locked and will open, as opposed to a door that they will never open?

Does a player know how to unlock a door? Do they need a key? To hack a console? To solve a puzzle? To wait until a story moment passes?

Are there doors that can open but the player can never enter them?

Where do enemies come from? Do they run in from doors? Do those doors lock afterwards?

How does the player open a door? Do they just walk up to it and it slides open? Does it swing open? Does the player have to press a button to open it?

Do doors lock behind the player?

What happens if there are two players? Does it only lock after both players pass through the door?

What if the level is REALLY BIG and can’t all exist at the same time? If one player stays behind, the floor might disappear from under them. What do you do?

Do you stop one player from progressing any further until both are together in the same room?

Do you teleport the player that stayed behind?

What size is a door?

Does it have to be big enough for a player to get through?

What about co-op players? What if player 1 is standing in the doorway — does that block player 2?

What about allies following you? How many of them need to get through the door without getting stuck?

What about enemies? Do mini-bosses that are larger than a person also need to fit through the door?

In the context of digital video games, we can think of the game as a SoS, but we also need to consider the systems on which the game is played, such as a gaming console, a personal computer, or a mobile device, and the peripherals used to interact with these games.

Since game systems can be developed independently, they are typically worked on by dispersed individuals grouped into specialized teams. Game designers often work on their systems in isolation for years at a time. Time is generally the driving force behind this type of specialization.

If you have the lifespan of a Tolkien elf and can potentially work on your independent game for a century, that’s fine. However, if you have less time to put out your game, you will need to speed things up by undertaking a lot of delegation, in which teams focus on various sub-components of the game in different workflows from one another.

Procedural World Systems

Real-time procedurally generated gaming worlds are known as “procedural worlds.” Real-time system output for any type of game component, including infinite landscapes, characters, vehicles, and buildings, is determined by a set of parameters.

In computing, procedural generation is a method of creating data algorithmically as opposed to manually, typically through a combination of human-generated assets and algorithms coupled with computer-generated randomness and processing power. In computer graphics, it is commonly used to create textures and 3D models. In video games, it is used to automatically create large amounts of content in a game.
Depending on the implementation, advantages of procedural generation can include smaller file sizes, larger amounts of content, and randomness for less predictable gameplay. Procedural generation is a branch of media synthesis.
— “Procedural generation,” Wikipedia

Emergent Systems

An emergent property of a system is a characteristic of the system as a whole that does not exist in any of its individual parts. Since game mechanics can interact with one other in addition to player input, emergence occurs in games.

Conway’s Game of Life is a classic example of emergence since it shows how a few basic rules may lead to surprisingly complex patterns on a grid:

A cell is born when exactly three neighbors become populated with a cell.

A cell that shares its border with two or three other cells survives to the following round.

Cells with fewer than two neighbors die.

A cell with more than three neighbors dies from overcrowding.

Open World Games

An open-world or free-roaming game is a type of video game that allows players to explore and interact with a virtual world that is not confined to a linear path or story. These games typically offer a large, open environment that players can explore and navigate at their own pace.

Some common features of open-world games include non-linear gameplay, where players can choose their own goals and objectives; a vast game world with numerous locations to visit and activities to participate in; and the ability to freely roam and explore the game world without being restricted by artificial barriers or boundaries.

Examples of open-world games include:

Grand Theft Auto
The Legend of Zelda: Breath of the Wild
The Elder Scrolls series (e.g. Skyrim)
Far Cry
Red Dead Redemption
Assassin’s Creed
Just Cause

Finite State Machines

A finite state machine (FSM) is a type of artificial intelligence (AI) architecture that is commonly used in video games to control the behavior of non-player characters (NPCs). It is called a “finite” state machine because it can only be in one of a finite number of states at any given time.

An NPC’s state machine can be defined in a state chart using the universal modeling language (UML). A state chart is a diagram that represents the different states that an NPC can be in and the transitions between those states. Each state is represented by a circle, and the transitions between states are represented by arrows. The conditions that trigger a transition from one state to another can be defined using boolean logic or other rules.

FSMs are popular in game AI because they are relatively simple to design and implement, and they can be used to create complex behavior for NPCs. They are particularly well-suited for situations where an NPC’s behavior can be divided into discrete, well-defined states, such as idle, attacking, or searching for the player.

FSMs can be used to control other aspects of a game as well, such as the behavior of objects or the flow of the game itself. However, they are most commonly used for controlling NPC behavior.

A finite state machine (sometimes called a finite state automaton) is a computation model that can be implemented with hardware or software and can be used to simulate sequential logic and some computer programs. Finite state automata generate regular languages. Finite state machines can be used to model problems in many fields including mathematics, artificial intelligence, games, and linguistics.
A finite state machine (sometimes called a finite state automaton) is a computation model that can be implemented with hardware or software and can be used to simulate sequential logic and some computer programs. Finite state automata generate regular languages. Finite state machines can be used to model problems in many fields including mathematics, artificial intelligence, games, and linguistics.
— “finite state machine,” brilliant.org

Bibliography & Further Reading

A Game Design Vocabulary: Exploring the Foundational Principles Behind Good Game Design by Anna Anthropy and Naomi Clark
A Theory of Fun for Game Design by Raph Koster
Advanced Game Design: A Systems Approach by Michael Sellers
An Introduction to Game Studies by Frans Mayra
Basics of Game Design by Michael Moore
Blood, Sweat, and Pixels: The Triumphant, Turbulent Stories Behind How Video Games Are Made Blood, Sweat, and Pixels: The Triumphant, Turbulent Stories Behind How Video Games Are Made by Jason Schreier
Board Game Design Advice: From the Best in the World vol 1 by Gabe Barrett
Building Blocks of Tabletop Game Design: an Encyclopedia Of Mechanisms by Geoffrey Engelstein and Isaac Shalev
Character Development and Storytelling for Games by Lee Sheldon
Chris Crawford on Game Design by Chris Crawford
Clockwork Game Design by Keith Burgun
Elements of Game Design by Robert Zubek
Fundamentals of Game Design by Ernest Adams
Fundamentals of Puzzle and Casual Game Design by Ernest Adams
Game Design Foundations by Brenda Romero
Game Design Workshop by Tracy Fullerton
Game Mechanics: Advanced Game Design by Ernest Adams and Joris Dormans
Game Writing: Narrative Skills for Videogames edited by Chris Bateman
Games, Design and Play: A detailed approach to iterative game design by Colleen Macklin and John Sharp
Introduction to Game Systems Design by Dax Gazaway
Kobold Guide to Board Game Design by Mike Selinker, David Howell, et al
Kobold’s Guide to Worldbuilding edited by Janna Silverstein
Level Up! The Guide to Great Video Game Design, 2nd Edition by Scott Rogers
Narrating Space / Spatializing Narrative: Where Narrative Theory and Geography Meet by Marie-Laure Ryan, Kenneth Foote, et al.
Narrative Theory: A Critical Introduction by Kent Puckett
Narrative Theory: Core Concepts and Critical Debates by David Herman, James Phelan, et al.
Narratology: Introduction to the Theory of Narrative, Fourth Edition by Mieke Bal
Practical Game Design by Adam Kramarzewski and Ennio De Nucci
Procedural Storytelling in Game Design by Tanya X. Short and Tarn Adams
Professional Techniques for Video Game Writing by Wendy Despain
Rules of Play by Salen and Zimmerman
Storyworlds Across Media: Toward a Media-Conscious Narratology (Frontiers of Narrative) by Marie-Laure Ryan, Jan-Noël Thon, et al
Tabletop Game Design for Video Game Designers by Ethan Ham
The Art of Game Design, 3rd Edition by Jesse Schell
The Board Game Designer’s Guide: The Easy 4 Step Process to Create Amazing Games That People Can’t Stop Playing by Joe Slack
The Cambridge Introduction to Narrative by H. Porter Abbott
The Grasshopper, by Bernard Suits
The Routledge Companion to Video Game Studies by Bernard Perron and Mark J.P. Wolf
The Routledge Encyclopedia of Narrative Theory by David Herman
The Ultimate Guide to Video Game Writing and Design by Flint Dille & John Zuur Platten
Unboxed: Board Game Experience and Design by Gordon Calleja
Video Game Storytelling: What Every Developer Needs to Know about Narrative Techniques by Evan Skolnick
Writing for Video Game Genres: From FPS to RPG edited by Wendy Despain
Writing for Video Games by Steve Ince
100 Principles of Game Design by DESPAIN