How to add @duel for the normal players

[IvanD]

What’s else do I need ?

[shatowolf]

25 minutes ago, IvanD said:

What’s else do I need ?

groups.conf   

@duel {<player name>} - Enables duel mode, if a valid name is provided, the player will be sent an invite to duel.
@invite <player name> - Invites a player to duel.
@accept - Accepts a duel invitation.
@reject - Rejects a duel invitation.
@leave - Leaves duel mode.