Her article is 5 years old now but is still holds great advice and teachings on how to write a good game design document.
“Before you start writing, consider is your audience. Many new designers write documents as if they’re being written for gamers instead of a programmer who’s tired, annoyed and up at 3 a.m. coding your combat system. The latter is your audience. Statements like, “Cannons allow you to blast your enemies to pieces!” shouldn’t be in design documents. Save that for the back of the box. Try something like this instead: “Each cannon has four shots before it must be reloaded. Cannons are reloaded automatically, provided there is ammo available and a pirate is available to reload it. If no ammo is available…”
“When creating a core statement for a game, sometimes game developers take themselves too seriously. They try to sound too important or profound. Some think that their statement doesn’t sound fun at all. Some may even go so far as to think that their statement sounds silly, and some cores actually do! However, they make for fabulous games. Katamari Damacy’s statement is this: Katamari Damacy is about rolling over things, picking them up and collecting them. Never underestimate the potential of any core, particularly yours.”
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