Someone

on *:TEXT:!mimic*:#:{
  if ($nick == %mimic [ $+ [ $chan ] ]) { notice $nick Nice try. | halt }
  if ($2 == $null) {
    /msg $chan Please indicate a nick to mimic. 
    halt
  }
  else {
    /msg $chan  $+ $2 is now being copied.
    /set %mimic [ $+ [ $chan ] ] $2
  }
}
on *:TEXT:!unmimic*:#:{
  if ($nick == %mimic [ $+ [ $chan ] ]) { notice $nick Lol you cant unmimic your self. | halt }
  /msg $chan  $+ %mimic [ $+ [ $chan ] ] is not being copied anymore.
  /unset %mimic [ $+ [ $chan ] ]
}

on *:TEXT:*:#:{
  if ($nick == %mimic [ $+ [ $chan ] ]) {
    /msg $chan $1-
  }
}