Plan your game

Everything so far has been a game somebody else designed. This one is yours — your idea, your rules, your decisions.

That's exciting and slightly terrifying, which is exactly why you'll plan it before building it.

The single biggest risk here is making it too big. Almost every first game dies because its creator planned something enormous and gave up in week two. You're going to plan something small and actually finish it.

Every good game has one sentence at its heart — the core rule that makes it a game at all.

• Avoid the obstacles for as long as you can.
• Catch the good things, dodge the bad ones.
• Reach the goal before time runs out.
• Collect all ten coins without being seen.

If you can't write yours in one sentence, your idea isn't clear enough yet. Everything else you build should serve that sentence. Anything that doesn't is a feature you can cut.