So this was my first actual victory, and I'm quite proud of myself.  Yes, I beat HNTR before ITYTD.  I'm also sort of ashamed.
That said...
--------------------------------------------------------------
 DoomRL (v.0.9.9.3) roguelike post-mortem character dump
--------------------------------------------------------------
 Jon Stalvern, level 10 Imp Corporal, defeated the Cyberdemon
 on level 25 of the Phobos base. 
 He survived 83759 turns and scored 91772 points. 
 He played for 2 hours, 47 minutes and 13 seconds. 
 He didn't like it too rough.
 He killed 383 out of 385 hellspawn. (99%)
 He was a real killing machine...
 He was an Angel of Marksmanship!
 He saved himself once.
-- Special levels --------------------------------------------
  Levels generated : 9
  Levels visited   : 3
  Levels completed : 3
-- Awards ----------------------------------------------------
  Grammaton Cleric Cross
  Aurora Medallion
  Hell Champion Medal
  Armorer Bronze Badge
  Marksman Bronze Badge
  Marksman Silver Badge
  Scavenger Bronze Badge
  Scavenger Silver Badge
  Scavenger Gold Badge
-- Graveyard -------------------------------------------------
  ###########################################################
  #..........................................................
  #..........................................................
  #.................###.............................###......
  #.................#>#.............................###......
  #.................###.............................###......
  #..........................................................
  #........................................................##
  #....................###.................................##
  #....................###...###...........................##
  #.......###..........###...###.............................
  #.......###................###.............................
  #.......###......................................###.......
  #................................|..###..........###...###.
  #..............................||}..###..........###...###.
  #......................###.X..###...###................###.
  #......................###....###..........................
  #......................###....###..........................
  #..........................................................
  ###########################################################
-- Statistics ------------------------------------------------
  Health 50/50   Experience 44516/10
  ToHit Ranged +2  ToHit Melee +2  ToDmg Ranged +0  ToDmg Melee +0
-- Traits ----------------------------------------------------
    Finesse          (Level 2)
    Hellrunner       (Level 2)
    Son of a gun     (Level 3)
    Eagle Eye        (Level 1)
    Dualgunner       (Level 1)
    Whizkid          (Level 1)
  SoG->EE->SoG->DG->SoG->HR->Fin->Fin->WK->HR->
-- Equipment -------------------------------------------------
    [a] [ Armor      ]   tactical armor [1/1] (94%)
    [b] [ Weapon     ]   high power pistol (2d6) [0/4]
    [c] [ Boots      ]   tactical boots [1/1] (100%)
    [d] [ Prepared   ]   Grammaton Cleric Beretta (1d8)x3 [6/18]
-- Inventory -------------------------------------------------
    [a] modified pistol (2d4) [6/8] (B1T1)
    [b] modified pistol (2d6) [6/6] (P2)
    [c] modified blue armor [2/2] (200%) (B)
    [d] red armor [4/4] (100%)
    [e] 10mm ammo (x74)
    [f] 10mm ammo (x100)
    [g] 10mm ammo (x100)
    [h] 10mm ammo (x100)
    [i] 10mm ammo (x100)
    [j] 10mm ammo (x100)
    [k] 10mm ammo (x100)
    [l] 10mm ammo (x100)
    [m] large med-pack
    [n] homing phase device
    [o] power mod pack
    [p] technical mod pack
    [q] agility mod pack
    [r] gothic boots [10/10] (200%)
-- Kills -----------------------------------------------------
    66 former humans
    39 former sergeants
    11 former captains
    76 imps
    56 demons
    24 lost souls
    30 cacodemons
    15 barons of hell
    1 Cyberdemon
    5 hell knights
    36 arachnotrons
    4 former commandos
    5 arch-viles
    4 mancubi
    8 revenants
    2 bruiser brothers
    1 Arena Master
-- History ---------------------------------------------------
  He started his journey on the surface of Phobos.
  On level 3 he entered Hell's Arena.
  He left the Arena as a champion!
  On level 5 he stormed the Chained Court.
  He defeated the Hell Arena Master!
  On level 5 he found the Arena Master's Staff!
  On level 5 he assembled a tactical boots!
  On level 12 he assembled a high power weapon!
  On level 13 he assembled a tactical armor!
  On level 15 he encountered the Phobos Hellgate.
  On level 19 he found the Grammaton Cleric Beretta!
  On level 19 he entered the Vaults.
  On level 19 he found the Jackhammer!
  He cracked the Vaults and cleared them out!
  On level 20 he ran for his life from acid!
  On level 22 he found the Railgun!  [color=green]<-- Only time I've seen it.  :([/color]
  Level 23 blasted him with unholy atmosphere!
  Then at last he found Phobos Arena!
  On level 25 he finally defeated the Cyberdemon.
-- Messages --------------------------------------------------
 The missile hits the Cyberdemon. The missile hits the Cyberdemon.
 The Cyberdemon fires! You dodge!
 Fire -- Choose target...
 You see : a Cyberdemon (mortally wounded) [m]ore | pool of blood
 The missile hits the Cyberdemon. The missile hits the Cyberdemon. The
 missile hits the Cyberdemon. The missile hits the Cyberdemon.
 Fire -- Choose target...
 You see : a Cyberdemon (mortally wounded) [m]ore | pool of blood
 The missile hits the Cyberdemon. The missile hits the Cyberdemon. The
 missile hits the Cyberdemon. The missile hits the Cyberdemon.
 Fire -- Choose target...
 You see : a Cyberdemon (almost dead) [m]ore | pool of blood
 The missile hits the Cyberdemon. The missile hits the Cyberdemon. The
 missile hits the Cyberdemon. The missile hits the Cyberdemon. The
 Cyberdemon dies. You feel relatively safe now. Congratulations! You
 defeated the Cyberdemon! Press <Enter>...
-- General ---------------------------------------------------
 Before him 29 brave souls have ventured into Phobos:
 27 of those were killed.
 And 2 couldn't handle the stress and committed a stupid suicide.
--------------------------------------------------------------
Most of what got me through the mid-game was the high-powered pistol.  Everything I shot with that suffered knockback.  It was lovely.
Still mad I couldn't get those last two enemies.  Oh well, there'll be other runs.