A member will be allowed to create a team if and only if they are a Sophomore ranked in Ra Yellow (or whatever the second rank dorm will be know as at the time). To have a team approved to enter Team Duals, a MINIMUM of 5 members must have joined the team. The creator of the team can make whatever requirements to join that he or she wishes.
Anyone can join a team as long as they meet the requirements. Requirements can be anything such as: Deck-type, Dorm Rank, Year Rank, Level, Reputation, etc. Each dormitory will have teams within it created by me and can be joined if you are within that dorm.