One of the big 7 questions.
2 Answers
To start generic: - A list of questions that are allowed and what not. - Some guidelines on how to ask and answer a question. - Of course the standard SO mechanics. - Names and task of the moderators.
@Gamecat has some good suggestions. I'd add (I'll update this if i think of more):
- When a question should be in meta.
- When a question should be in gaming.stackexchange.com.
- Profanity policy, if any.