Someone

on $*:TEXT:/^!set(pcw|world|pc)/Si:*:{
  if ($nick isop $chan) {
    set %pcw $2 | set %setnick $nick | set %settime $ctime
    msg $chan New world set by $nick $+ ! Type !pcw or !world to get it
  }
}

on $*:TEXT:/^!(pcw|world)/Si:#:{
  if ($nick !isreg $chan) {
    notice $nick World is %pcw
    notice $nick World was set by %setnick about $duration($calc($ctime - %settime)) ago
  }
}