The following NPCs can be found in the Undercity.

Questgivers

Horde

•  Alessandro Luca <Blue Moon Odds and Ends>
  •  [45] Errand for Apothecary Zinge (2)
•  Ambassador Sunsorrow
  •  [15] Delivery to the Sepulcher
  •  [20] Report to Tarren Mill
•  Anastasia Hartwell <Mage Trainer>
  • [10] The Balnir Farmstead
  • [16] Investigate the Alchemist Shop
  • [38] Journey to the Marsh
  • [40] Return to the Marsh
•  Andrew Brownell
  •  [42] Bring the End (Dungeon)
•  Andron Gant
  • [15] The Deathstalkers (3)
  •  [52] Andron's Payment to Jediga
•  Apothecary Zinge <Royal Apothecary Society>
  •  [15] Sample for Helbrim
  •  [45] Errand for Apothecary Zinge
  •  [46] Into the Field
  •  [55] Vivian Lagrave
  •  [60] Vivian Lagrave and the Darkstone Tablet
•  Baltus Fowler <Warrior Trainer>
  • [30] The Islander
•  Bethor Iceshard
  •  [8] The Lich's Identity
  •  [8] Return the Book
  •  [16] Thule Ravenclaw
•  Bragor Bloodfist
  •  [16] The Power to Destroy...
  •  [36] An Unholy Alliance (2)
  •  [42] Into The Scarlet Monastery
  •  [60] The Crimson Courier
•  Carendin Halgar
  • [10] Creature of the Void (Undercity)
  • [10] The Binding
  • [20] Hearts of the Pure
  • [20] The Binding
•  Chemist Cuely
  •  [52] Seeping Corruption (1)
  •  [52] Seeping Corruption (2)
  •  [52] Seeping Corruption (3)
•  Chemist Fuely
  •  [52] A Sample of Slime...
  •  [56] ... and a Batch of Ooze
  •  [56] Melding of Influences
•  Genavie Callow
  •  [36] To Steal From Thieves
•  Gordon Wendham <Weapons Merchant>
  •  [10] Michael Garrett
•  Harbinger Balthazad
  •  [50] A Call to Arms: The Plaguelands! (Horde)
  •  [55] The New Frontier
  •  [57] Camp Mojache
•  Horde Warbringer
  •  [70] Call to Arms: Warsong Gulch (Horde) (PvP, Daily)
  •  [70] Call to Arms: Arathi Basin (Horde) (PvP, Daily)
  •  [70] Call to Arms: Alterac Valley (Horde) (PvP, Daily)
  •  [70] Call to Arms: Eye of the Storm (Horde) (PvP, Daily)
•  Innkeeper Norman <Innkeeper>
  •  [50] Assisting Arch Druid Runetotem
  •  [60] Chicken Clucking for a Mint (Hallow's End)
•  Jeremiah Payson <Cockroach Vendor>
  •  [52] Good Luck Charm
•  Jorah Annison
  • [30] Tome of the Cabal
•  Josef Gregorian <Artisan Tailor>
  • [15] Gathering Materials
  • [15] Spellfire Robes
•  Keeper Bel'dugur
  •  [26] The Book of Ur
  •  [40] Forbidden Knowledge
  •  [44] The Star, the Hand and the Heart (Elite)
•  Kwee Q. Peddlefeet (Love is in the Air)
  • ...
•  Lady Sylvanas Windrunner <Banshee Queen>
  •  [21] Meeting the Warchief
  •  [56] The Champion of the Banshee Queen
•  Lunar Festival Harbinger (Lunar Festival)
  •  [70] Lunar Fireworks (Lunar Festival)
  •  [70] Valadar Starsong (Lunar Festival)
•  Lunar Festival Herald (Lunar Festival)
  •  [70] The Lunar Festival (Lunar Festival)
•  Master Apothecary Faranell <Royal Apothecary Society>
  •  [15] A Recipe For Death (2)
  •  [30] Elixir of Agony (3)
  •  [33] Going, Going, Guano! (Dungeon)
  •  [33] Hearts of Zeal (Dungeon)
•  Mennet Carkad
  • [13] The Deathstalkers
  • [13] The Deathstalkers (2)
  • [13] The Deathstalkers (4)
  • [16] Fenwick Thatros
  • [20] Tools of the Trade
•  Michael Garrett <Bat Handler>
  •  [10] Return to Podrig
•  Nardstrum Copperpinch <Smokywood Pastures> (Feast of Winter Veil)
  •  [60] Great-father Winter is Here! (Feast of Winter Veil)
•  Officer Gothena <Undercity Commendations>
  •  [60] One Commendation Signet (Repeatable)
  •  [60] Ten Commendation Signets (Repeatable)
•  Oran Snakewrithe
  •  [47] Lines of Communication
•  Parqual Fintallas
  •  [36] Test of Lore (4) (Dungeon)
  •  [36] Test of Lore (5)
  •  [36] Final Passage
•  Patrick Garrett
  •  [43] Reclaimed Treasures (Dungeon)
•  Raleigh Andrean <Ex-Chef>
  •  [20] A Husband's Revenge
•  Ralston Farnsley <Horde Cloth Quartermaster>
  •  [60] A Donation of Wool
  •  [60] A Donation of Silk
  •  [60] A Donation of Mageweave
  •  [60] A Donation of Runecloth
  •  [60] Additional Runecloth (Repeatable)
•  Royal Overseer Bauhaus <Undercity Census>
  •  [52] The Jeremiah Blues
•  Senior Sergeant Grimsford <War Effort Recruiter> (Ahn'Qiraj War Effort)
  •  [60] The Horde Needs Your Help! (Ahn'Qiraj War Effort)
•  Sharlindra
  •  [30] The Crown of Will
•  Varimathras
  •  [16] The Power to Destroy... (Dungeon)
  •  [36] An Unholy Alliance (2) (Dungeon)
  •  [42] Into The Scarlet Monastery (Dungeon)
  •  [60] The Crimson Courier (Elite)
•  Velora Nitely
  • [30] Brutal Legguards
  • [30] Dragonmaw Shinbones

Neutral

•  Elder Darkcore (Lunar Festival)
  •  [70] Darkcore the Elder (Lunar Festival)

Class Trainers

Horde

•  Aelthalyste <Priest Trainer>
  •  Father Lazarus <Priest Trainer>
    •  Father Lankester <Priest Trainer>
•  Champion Cyssa Dawnrose <Paladin Trainer>
•  Christoph Walker <Warrior Trainer>
  •  Angela Curthas <Warrior Trainer>
    •  Baltus Fowler <Warrior Trainer>
•  Gregory Charles <Rogue Trainer>
  •  Miles Dexter <Rogue Trainer>
    •  Carolyn Ward <Rogue Trainer>
•  Kaal Soulreaper <Warlock Trainer>
  •  Luther Pickman <Warlock Trainer>
    •  Richard Kerwin <Warlock Trainer>
      •  Martha Strain <Demon Trainer>
•  Kaelystia Hatebringer <Mage Trainer>
  •  Pierce Shackleton <Mage Trainer>
    •  Anastasia Hartwell <Mage Trainer>
      •  Lexington Mortaim <Portal Trainer>

Profession (Tradeskill) Trainers

Horde

•  Armand Cromwell <Fishing Trainer>
•  Arthur Moore <Leatherworking Trainer>
•  Brom Killian <Mining Trainer>
•  Doctor Herbert Halsey <Alchemy Trainer>
•  Eunice Burch <Cooking Trainer>
•  Franklin Lloyd <Engineering Trainer>
•  James Van Brunt <Blacksmithing Trainer>
•  Josef Gregorian <Tailoring Trainer>
•  Killian Hagey <Skinning Trainer>
•  Lavinia Crowe <Enchanting Trainer>
•  Martha Alliestar <Herbalism Trainer>
•  Mary Edras <First Aid Trainer>

Merchants

Horde

•  Abigail Sawyer <Bow Merchant>
•  Alessandro Luca <Blue Moon Odds and Ends>
•  Algernon <Alchemy Supplies>
•  Benijah Fenner <Weapon Merchant>
•  Charles Seaton <Blade Merchant>
•  Daniel Bartlett <General Trade Supplier>
•  Eleanor Rusk <General Goods Vendor>
•  Elizabeth Van Talen <Engineering Supplier>
•  Ezekiel Graves <Poison Vendor>
•  Felicia Doan <General Trade Goods Vendor>
•  Francis Eliot <Weapon Merchant>
•  Geoffrey Hartwell <Weapon Merchant>
•  Gillian Moore <Leather Armor Merchant>
•  Gordon Wendham <Weapons Merchant>
•  Hannah Akeley <Reagent Supplier>
•  Jaycrue Copperpinch <Smokywood Pastures> (Feast of Winter Veil)
•  Jeremiah Payson <Cockroach Vendor>
•  Jonathan Chambers <Bag Vendor>
•  Joseph Moore <Leatherworking Supplies>
•  Katrina Alliestar <Herbalism Supplier>
•  Lauren Newcomb <Light Armor Merchant>
•  Lizbeth Cromwell <Fishing Supplier>
•  Louis Warren <Weapons Merchant>
•  Lucille Castleton <Robe Vendor>
•  Lunar Festival Vendor (Lunar Festival)
•  Merill Pleasance <Tabard Vendor>
•  Millie Gregorian <Tailoring Supplies>
•  Mirelle Tremayne <Heavy Armor Merchant>
•  Morley Bates <Fungus Vendor>
•  Nardstrum Copperpinch <Smokywood Pastures> (Feast of Winter Veil)
•  Nathaniel Steenwick <Thrown Weapons Merchant>
•  Nicholas Atwood <Gun Merchant>
•  Ronald Burch <Cooking Supplier>
•  Salazar Bloch <Book Dealer>
•  Samuel Van Brunt <Blacksmithing Supplier>
•  Sarah Killian <Mining Supplier>
•  Sheldon Von Croy <Cloth Armor Merchant>
•  Sydney Upton <Staff Merchant>
•  Tawny Grisette <Mushroom Vendor>
•  Thaddeus Webb <Enchanting Supplies>
•  Thomas Mordan <Reagent Vendor>
•  Timothy Weldon <Heavy Armor Merchant>
•  Walter Ellingson <Heavy Armor Merchant>
•  Zane Bradford <Wand Vendor>

Various Services

Horde

•  Anya Maulray <Stable Master>
•  Archibald <Weapon Master>
•  Auctioneer Cain - (Auctioneer)
•  Auctioneer Epitwee - (Auctioneer)
•  Auctioneer Leeka - (Auctioneer)
•  Auctioneer Naxxremis - (Auctioneer)
•  Auctioneer Rhyker - (Auctioneer)
•  Auctioneer Stockton - (Auctioneer)
•  Auctioneer Tricket - (Auctioneer)
•  Auctioneer Yarly - (Auctioneer)
•  Christopher Drakul <Guild Master>
•  Defilers Emissary - (Arathi Basin Recruiter) (Call to Arms: Arathi Basin)
•  Edward Remington <Guild Tabard Designer>
•  Eye of the Storm Envoy - (Eye of the Storm Recruiter) (Call to Arms: Eye of the Storm)
•  Frostwolf Emissary - (Alterac Valley Recruiter) (Call to Arms: Alterac Valley)
•  Grizzle Halfmane <Alterac Valley Battlemaster>
•  Innkeeper Norman <Innkeeper>
•  Kraxx <Zeppelin Engineer>
•  Kurden Bloodclaw <Warsong Gulch Battlemaster>
•  Lyrlia Blackshield <Eye of the Storm Battlemaster>
•  Michael Garrett <Bat Handler>
•  Mortimer Montague <Banker>
•  Ophelia Montague <Banker>
•  Randolph Montague <Banker>
•  Rex Pixem <Arena Battlemaster>
•  Sir Malory Wheeler <Arathi Basin Battlemaster>
•  Undercity Guardian - (Directions)
•  Warsong Emissary - (Warsong Gulch Recruiter) (Call to Arms: Warsong Gulch)
•  William Montague <Banker>

Inhabitants

•  Samantha Shackleton