Mine

on $*:TEXT:/^[!.]duel [wmr]/Si:#:{
  if (%duel. [ $+ [ $chan ] ] == on) { .notice $nick $+($c1(There is already a),$chr(32),$c2(duel),$chr(32),$c1(in progress)) | halt }
  else {
    if ($2 == w) {
      msg $chan $+($c1($nick has initiated a),$chr(32),$c2(dds + whip),$chr(32),$c1(duel, type),$chr(32),$c2(!duel w),$chr(32),$c1(to join in the duel))
      set %w1. [ $+ [ $chan ] ] $nick
      set %dwait. [ $+ [ $chan ] ] on
      set %fight. [ $+ [ $chan ] ] meele  
    }
    else {    
      if (%dwait. [ $+ [ $chan ] ] == on) && ($2 == w) && ($nick != %w1. [ $+ [ $chan ] ]) {
        set %dwait. [ $+ [ $chan ] ] off
        set %wspec1. [ $+ [ $chan ] ] 4
        set %wspec2. [ $+ [ $chan ] ] 4
        set %whp1. [ $+ [ $chan ] ] 99
        set %whp2. [  $+ [ $chan ] ] 99    
        set %w2. [ $+ [ $chan ] ] $nick
        set %duel. [ $+ [ $chan ] ] on
        msg $chan $+($c1(The duel is on),$chr(32),$c2(%w1),$chr(32),$c1(VRS),$chr(32),$c2(%w2),$chr(32),$c1(- For help type !duelhelp))
        set %first. [ $+ [ $chan ] ] $r(1,5)
        if (%first. [ $+ [ $chan ] ] isnum 1-3) { msg $chan $+($c2(%w1),$chr(32),$c1(goes first!)) | halt }
        elseif (%first. [ $+ [ $chan ] ] isnum 4-5) { msg $chan $+($c2(%w2),$chr(32),$c1(goes first!)) | halt }
        halt      
      }
      elseif ($2 == r) {
        msg $chan $+($c1($nick has initiated a),$chr(32),$c2(range),$chr(32),$c1(duel, type),$chr(32),$c2(!duel r),$chr(32),$c1(to join in the duel))
        set %r1. [ $+ [ $chan ] ] $nick
        set %fight. [ $+ [ $chan ] ] ranged  
        set %dwait. [ $+ [ $chan ] ] on
      }
      if (%dwait. [ $+ [ $chan ] ] == on) && ($2 == r) && ($nick != %r1. [ $+ [ $chan ] ]) {
        set %dwait. [ $+ [ $chan ] ] off
        set %ammo1. [ $+ [ $chan ] ] 5
        set %ammo2. [ $+ [ $chan ] ] 5
        set %r2. [ $+ [ $chan ] ] $nick
        set %rhp1. [ $+ [ $chan ] ] 99
        set %rhp2. [ $+ [ $chan ] ] 99    
        set %duel. [ $+ [ $chan ] ] on
        msg $chan $+($c1(The duel is on),$chr(32),$c2(%r1),$chr(32),$c1(VRS),$chr(32),$c2(%r2),$chr(32),$c1(- For help type !duelhelp))
        set %first. [ $+ [ $chan ] ] $r(1,5)
        if (%first. [ $+ [ $chan ] ] isnum 1-3) { msg $chan $+($c2(%r1),$chr(32),$c1(goes first!)) }
        elseif (%first. [ $+ [ $chan ] ] isnum 4-5) { msg $chan $+($c2(%r2),$chr(32),$c1(goes first!)) }
        halt      
      }
      elseif ($2 == m) {
        msg $chan $+($c1($nick has initiated a),$chr(32),$c2(magic),$chr(32),$c1(duel, type),$chr(32),$c2(!duel m),$chr(32),$c1(to join in the duel))
        set %m1. [ $+ [ $chan ] ] $nick
        set %fight. [ $+ [ $chan ] ] magic    
        set %dwait. [ $+ [ $chan ] ] on
      }
      if (%dwait. [ $+ [ $chan ] ] == on) && ($2 == m) && ($nick != %m1. [ $+ [ $chan ] ]) {
        set %dwait. [ $+ [ $chan ] ] off
        set %m2. [ $+ [ $chan ] ] $nick
        set %mhp1. [ $+ [ $chan ] ] 99
        set %mhp2. [ $+ [ $chan ] ] 99
        set %duel. [ $+ [ $chan ] ] on
        msg $chan $+($c1(The duel is on),$chr(32),$c2(%r1),$chr(32),$c1(VRS),$chr(32),$c2(%r2),$chr(32),$c1(- For help type !duelhelp))
        set %first. [ $+ [ $chan ] ] $r(1,5)
        if (%first. [ $+ [ $chan ] ] isnum 1-3) { msg $chan $+($c2(%m1),$chr(32),$c1(goes first!)) }
        elseif (%first. [ $+ [ $chan ] ] isnum 4-5) { msg $chan $+($c2(%m2),$chr(32),$c1(goes first!)) }
      }
    }
  }
}