Arena Rewards (source)

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Number Opponent Reward Number Opponent Reward
1 Noborta Kesyta, the Yeek President n/a 21 Biclops Potion: Self Knowledge
2 Mori Troll n/a 22 Mature multi-hued dragon Stack of Scrolls: Rune of Protection
3 Tiger n/a 23 Halfling slinger n/a
4 Druid n/a 24 Elder thing Wand: Drain Life (6/6)
5 Hill giant Stack of Potions: Speed 25 Ettin Scroll: *Enchant Weapon*
6 Wererat n/a 26 Vampire lord Rod: Detection (2/2)
7 Orc captain n/a 27 Barney the Dinosaur Scroll: Genocide
8 Berserker Rod: Detect Traps (2/2) 28 Groo the Wanderer Stack of Scrolls: Mundanity
9 Stone giant n/a 29 Dark elven sorceror Wand: Meteor (6/6)
10 Dark elven lord Stack of Potions: Healing 30 Iron lich Potion: New Life
11 Iron golem n/a 31 Greater titan Potion: *Enlightenment*
12 Carrion crawler n/a 32 Greater balrog Rod: Enlightenment (2/2)
13 Xiclotlan n/a 33 Nightwalker Rod: Disintegration Beam (2/2)
14 Troll priest n/a 34 Shambler Staff: Holiness (6/6)
15 Angel Rod: Detect Monsters (2/2) 35 Black reaver Scroll: *Acquirement*
16 Spirit naga n/a 36 Fenghuang Staff: Restore Mana(6/6)
17 Basilisk n/a 37 Great Wyrm of Power Rod: Angelic Healing (2/2)
18 Mithril golem Wand: Acid Ball (6/6) 38 1 Million AU + Champion Status
19 Shadow drake n/a 39 The Metal Babble Scroll: Artifact Creation
20 Ogre shaman Scroll: Acquirement 40 ***TRUEWINNER***

Quest Rewards (source)

(Mayor)Thieves Hideout: {good} or {excellent} Class-suited item; or a {good} longsword for many classes
(Mayor)Warg Problem: {good} or {excellent} Class-suited item
(Mayor)Haunted House: Staff of Dispel Evil
(Mayor)Royal Crypt: Mithril Chain Mail of Bilbo
(Inn)Old Man Willow: Elemental Ring or Charm
(Inn)Dark Elven Lords: The Phial of Galadriel
(Inn)The Cloning Pits: {special} Class-suited item
(Inn)The Old Castle: {good} rare-base, device, or {special} Class-suited item
(Thieves' Guild)Tengu and Death Swords: Ring of Protection, Elemental Charm, or Dagger of Westernesse
(Thieves' Guild)The Mimic's Treasure: Ring of Protection or Amulet of Trickery
(Castle)Vapor Quest: Rod of Detection
(Castle)The Rise and Fall of Micro$oft: Ring or Amulet of Defender
(Castle)Doom Quest II: Staff of Healing
Orc Camp: a Cloak of Stealth
Doom Quest I: Elemental Ring or Charm
The Spawning Pits: Balance Dragon Scale Mail
The Sewer: Feanorian Lamp
Logrus Master: Rod: Chaos Strike
The Vault: n/a (Sting is a guaranteed spawn in the level)
The Barrow Downs: Discount at Library, Beastmaster, and Weaponmaster (Cloak of Merry is a guaranteed spawn in the level)
Assault on Montsalvat: Hell Harness
Killing Fields: Potion of Life
Eric's Stronghold: Potion of Augmentation
Node of Sorcery: Grimoire of Power
Node of Chaos: Armageddon Tome
Node of Nature: Nature's Wrath

Dungeons, Depth Ranges, Masters, and Rewards (source)

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Dungeon Depth Range Entrance Guardian Master Reward
Angband 1-127 n/a The Serpent of Chaos The Mighty Hammer, Grond & The Massive Iron Crown of Chaos
Camelot 20-35 n/a Arthur Pendragon a Mirror Shield
Orc Cave 10-23 n/a Azog, King of the Uruk-Hai a Ring of Combat
Labyrinth 20-28 n/a The Minotaur of the Labyrinth a Rod: Recall (2/2)
Dragon's Lair 60-72 Dracolisk Tiamat, Celestial Dragon of Evil a Wand: Rockets (8/8)
Graveyard 50-70 Master Lich Vecna, the Emperor Lich The Scimitar, Soulsword
Forest 20-32 n/a Shelob, Spider of Darkness a Poison Needle
Volcano 50-60 Lesser Balrog Shooting Star the Red Dragon a Staff: Mana Storm (6/6)
Hell 666-696 n/a n/a n/a
Heaven 555-585 n/a n/a n/a
Numenor 55-75 Lesser Kraken Jormungand the Midgard Serpent The Trifurcate Spear of Wrath
Castle 40-65 Anti-Paladin Layzark, the Emperor n/a
Rl'yeh 80-96 Warp Demon Great Cthulhu The Multi-hued Dragon Scale Mail 'Razorback'
Mountain 40-50 Jubjub Bird Thorondor a Potion: New Life
Mine 75-80 Elder Storm Giant n/a n/a
Anti-magic Cave 40-50 Juggernaut of Khorne n/a n/a
Anti-melee Cave 40-50 Bazooker n/a n/a
Chameleon Cave 30-45 n/a Chameleon Lord a Potion: Polymorph
Dark Cave 55-72 Shadowlord Null the Living Void The 4th book of your 1st school; otherwise Grimoire of Power
Glass Castle 40-60 Ethereal Dragon n/a n/a
Icky Cave 20-35 n/a Ubbo-Sathla, the Unbegotten Source a Ring
Mount Olympus 80-90 Sky Drake Zeus, King of the Olympians n/a
Lonely Mountain 30-40 n/a Smaug the Golden The 3rd book from your 1st school; otherwise Pattern Sorcery
Giant's Hall 30-40 n/a Utgard-Loke The Set of Gauntlets 'Paurnimmen'
Arena 50-80 Drolem Metal Babble Scroll: Artifact Creation
Stronghold 1-15 n/a Meng Huo, the King of Southerings an Amulet