FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
List Your Entities and Resources
Once you have your list of nouns, decide whether each represents a resource, an independent entity, an attribute of another entity—or perhaps none of the above, in which case, you can cross those off the list. Now you have a list of resources and entities. For each item on your list, consider these questions:
■ Does the noun describe a resource—some item or substance that changes in a general way throughout the game? Or does it describe an entity, a particular value, or quantity?
■ If the noun describes an entity, is the entity simple or compound? If simple, is it symbolic or numeric? If symbolic, what states can it take? If numeric, what is the range of numbers? What will its initial symbolic or numeric value be? These initial data form a critical part of the core mechanics that you will tune throughout the development process. Write them down in your document or in a spreadsheet.
■ If the noun describes a compound entity, what attributes describe it? (They might be elsewhere on the list, or you might have to invent some new ones.) Add any new attributes to your definition of the compound entity and go back to the previous question to determine their qualities.
Unless a game offers only one gameplay mode and no shell menus (which would be extremely rare), it will undoubtedly require an entity to record which gameplay mode or shell menu the game occupies at any given time.
This process will give you an initial list of all the resources and entities your game features. It won't be a complete list; you will undoubtedly add more as work goes on. If your early design stated generalities but not specifics, add the details now. Suppose you wrote, "Level 5 will consist mostly of formal logic puzzles." At this point, you must define the entities that the level designers will require to build the formal logic puzzles. Will the player drag tiles, flip switches, and click on colored marbles? Then add tiles, switches, and marbles to your list of entities. Now you've got some attributes to think about: The tiles have positions, the switches have states, and the marbles have colors. Write it all down.