Quotes from Ernest Adams

For a more detailed discussion of the subject, read Neal and Jana Hallford's Swords and Circuitry (Hallford and Hallford, 2001).

To keep the absolute difficulty level constant, whenever you increase the time pressure on a player, you should also reduce the amount of intrinsic skill required.

The relative difficulty is the difficulty of a challenge relative to the player's power to meet that challenge.

The level designers have to know, for example, that by the time the player reaches the fourth level, he will have earned three major weapon upgrades and a faster vehicle, so they set the difficulty of the fourth level's challenges relative to that level of power provided.

The perceived difficulty of a challenge—the difficulty that the player actually senses, and the type we are most concerned with—consists of the relative difficulty minus the player's experience at meeting such challenges. Remembering that relative difficulty is absolute difficulty minus power provided, we can put all these factors together into a single equation such that perceived difficulty = absolute difficulty - (power provided + in-game experience)

People love to design and create things, whether clothing, creatures, buildings, cities, or planets. They also love to customize a basic template of some kind to reflect their own choices.

Fundamental AI Technologies" in Core Techniques and Algorithms in Game Programming by Daniel Sánchez-Crespo Dalmau (Dalmau, 2004).

Sources If a resource or entity can come into the game world having not been there before, the mechanic by which it arrives is called a source.

Drains A drain is a mechanic that determines the consumption of resources—that is, a rule specifying how resources permanently drop out of the game (not to be confused with a converter, which we'll look at next). In a shooter game, the player firing his weapon drains ammunition—that's what makes ammunition, a resource, disappear. Being

Players don't mind getting money for free, but when they have to spend it, they want to know why. Explain your drains.

Production Mechanisms Production mechanism describes a class of mechanics that make a resource conveniently available to a player. These include sources that bring the resource directly into the player's hands, but they can also include special buildings, characters, or other facilities that gather resources from the landscape and make them available to the player.

In designing your game's internal economy, you need to watch out for deadlocks, which can occur whenever there's a loop in the production process. To avoid deadlocks, either avoid such loops or provide an alternative source for one of the resources.

Designing the core mechanics consists of identifying the key entities and mechanics in the game and writing specifications to document the nature of the entities and the functioning of the mechanics. This is the very heart of the game designer's job, and the more complex the game, the longer it takes—

Never forget that your ultimate goal is to create entertainment for the player—

In the most general sense, a balanced game is fair to the player (or players), is neither too easy nor too hard, and makes the skill of the player the most important factor in determining his success. In

Unless your game is a just-for-fun simulation such as Super Mario Kart or Beetle Adventure Racing!, vehicle simulation is the most technologically oriented of games, so the core mechanics of the game are almost entirely about physics.

Economies about money are called market economies. But we use the term in a more abstract way to refer to any kind of system in which resources—of any type—can be produced, exchanged, and consumed.

Entities that store one value are called simple entities. Compound entities are groups of related simple entities, so a compound entity can contain more than one value. For example, a unit in a strategy game normally includes many simple entities that describe its health, damage capability, maximum speed, and so on. Collectively, these make up a compound entity, and the simple entities that make it up are known as its attributes. Thus, a unit's health is an attribute of the unit.

You know, the suspension of disbelief is fragile. It's hard to achieve it and hard to maintain. One bit of unnecessary gore, one hip colloquialism, one reference to anything outside the imaginary world you've created is enough to destroy that world.

Don't confuse the term games of progression with other ideas about progression in games, such as leveling up, difficulty curves, skill trees, and so on. We use Juul's definition of the term: A game of progression is one that offers predesigned challenges, each of which often has exactly one solution, in a fixed (or only slightly variable) sequence.

In contrast, games of progression offer many predesigned challenges that the designer has ordered sequentially, usually through sophisticated level design.

Plan to throw away all sound, art, and code created for a prototype. That way your artists, audio people, and programmers can work quickly without worrying about having to debug their content later. Trying to build production-quality assets during preproduction just slows the process down. Once

A game concept is a description of a game detailed enough to begin discussing it as a potential commercial product—a piece of software that the public might want to buy.

Design Rule The Story Comes Later Do not spend a lot of time devising a story at the concept stage. This is a cardinal error frequently made by people who are more used to presentational media such as books and film. You must concentrate most of your efforts on the gameplay at this point. Types