Someone

on *:text:!setda*:#rsda,#rshelp: {
  if ($nick !isreg $chan) {
    set %daworld $2-
    set %danick $nick
    msg $chan Duel arena World Updated by: $nick
  }
}

on *:text:!da:#rsda: {
  notice $nick current world is %daworld set by %danick
}