Hogwarts Express employs two sets of code for Quidditch. The practice code, which will be used most often, is less strict and does not adhere to the full rules of Quidditch. This will allow players to try out different positions (thus using commands not normally theirs) or act more frequently than their team-members. The practice code does not keep track of such things as Bludger location, Quaffle location, who has spotted the Snitch and various other things.

The full game code requires two actual teams to be present, and unlike the practice code, it will keep track of the Bludgers, the Quaffle and the Snitch. It is very structured and very rigid, forcing players to adhere to one turn per round and enforcing consequences for mishaps (such as being hit with a Bludger or dropping the Quaffle). This system will only be brought out during scheduled game times and is initiated by the Referee.