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A user without a team can't do much. All the games belong to the teams, so unless a user is a member of a team, he neither would see any games, nor be able to join any.
Setting up a team
Go to the Team configuration (the link is located in the top menu)
Setting up a team is fairly simple — just click Create and start adding team members.
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He will receive an invitation email, which contains a link to join your team.
New user account will be automatically created.
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