There are some policies which apply across all Fandom. These can be found on Community Central in their policy category.
The local policy is a set of rules and procedures that add on to the global policy and make up the framework of the wiki. It is recommended that all members read and get to know and understand it before they begin editing. All sections of the policy apply to everyone under any circumstances, unless stated otherwise. It is the job of administrators to enforce policy, but all users can engage in encouraging adherence to it.
New policies for this wiki are suggested and decided by the community. It's generally best to keep policies as simple as possible, and not to introduce too many rules. A growing wiki can usually do well with a few simple policies and a lot of goodwill and cooperation.