This script detects "Nickname Highlight Spam" in IRC. Works in both mIRC and AdiIRC.

; $is_nickspam() - Nickname Highlight Spam Detector by Raccoon 2017.
; Parameters: $is_nickspam(<channel>,<text>,[M=6],[N=8])  eg: $is_nickspam($chan,$1-,6,8)  or just  $is_nickspam($chan,$1-)
;   Where M (>=2) is minimum nickname length to regard, and N (>=1) is number of matches considered as spammy.  Defaults: M = 6, N = 8.
; Returns: Number of positive nickname matches in the string, if it exceeds [N].  Returns 0 if less than [N]. 
; Note: This script looks at nickname parts that contain Letters, Numbers and Underscores, to detect variously decorated spam.
; Example Usage:  (Un-comment the next 5 lines to activate, and enjoy.)
; On @*:TEXT:????????????????????????????????????????????????????????????*:#: {
;   if ($nick !isop $chan) && (!$($+(%,_spamban.,$cid,$chan,$nick),2)) && ($is_nickspam($chan,$1-)) {
;     ban -k $chan $nick 2 Lame Highlight Spam Detected.
;     inc -z $+(%,_spamban.,$cid,$chan,$nick) 5
; } }
ALIAS is_nickspam { 
  var %chan = $$1, %text = $$2, %nicklen = $$iif($calc($3 -1) > 0,$v1,5), %nickspam = $$iif($calc($4) > 0,$v1,8)
  var %text = $mid($regsubex(is_nickspam,! %text !,/(*UTF8)(?:\W++|(?<!\w)(?:\w{1, $+ %nicklen $+ }|(\w++)(?=.*?\W\1(?:\W|$)))(?!\w))+/g,|),2,-1)
  if (%chan ischan) && ($numtok(%text,124) >= %nickspam) && ($fline(%chan,/(?<=^|\W)(?: $+ %text $+ )(?=\W|$)/i,0,3) >= %nickspam) { return $v1 }
  return 0
} ; by Raccoon 2017 Feb 28 - http://www.mpaste.com/p/Tu7NJh - http://hawkee.com/snippet/18055/