On $*:TEXT:/^[!@]Bl/Si:#:{
  set %blist $2
  set %reason $3-
  set %by $nick
.msg $chan %blist has been Blacklisted by --> %by <-- Reason: %reason }
}

on :JOIN:#:
If ($nick isin %blist) { ban -ku120 $chan $nick You are on the blacklist! Reason: %reason - You were added by %by
}