Chapter 7: Prototyping

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Overview

Prototyping lies at the heart of good game design. The word “prototyping” means to create a working version of the formal system that, while playable, includes only a rough approximation of the artwork, sound, and features. Think of it as a crude model whose purpose is to allow you to wrap your brain around the game mechanics and see how they function.

To many first-time designers, making prototypes seems cumbersome, but if you invest the time, you’ll discover that it teaches you about the essence of game design and that there is nothing more valuable for getting a game to work. You don’t get bogged down with production-related issues or distracted by the window dressing. All you have are the fundamental mechanics to keep you engaged, and if these mechanics can sustain the interest of playtesters, then you know that you’re onto something.

The main advantage of prototyping is that it forces you to define game mechanics in their purest form. If you look at most great games, the core gameplay is not complex. Studies show that human beings can, on average, track and manipulate seven concepts simultaneously. This was first established in 1956 by psychologist George Miller in his classic paper entitled “The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information.”^[1] In it, Miller showed 7 ±2 as the number of distinct items that humans can hold in short term memory. This strongly influenced the design of the U.S. phone system—e.g., phone numbers are seven digits long. Games utilize this concept successfully as well. For instance, the game Tetris includes seven shapes.

If you look carefully at games from Super Mario Bros. to Command & Conquer to Halo, you’ll see that underneath the amazing graphics and rich worlds, the gameplay is quite straightforward. These games are engaging largely because they are so easy to understand. In fact, we challenge you to take any addictive game and strip away the graphics, sound effects, and optional features. What you’ll find in almost every case is a system that can easily be modeled with a few basic rules. And this is why prototyping makes sense. It helps the game designer to focus on a handful of choices that the player must make and create a viable model for how the game will function given these limitations.

^[1]George Miller, “The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information,” Psychological Review, 1956 vol. 63, pp. 81–97.

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