We originally started this thread off here. But it's become a bit nebulous and unwieldy. Some of the things that were missing have been fixed, but many more remain on the "not fixed yet" pile. The current Offiical Known Issues List can be found here.
I'll use this first post as an index to the rest of the posts and copy them across from the other thread so we can just maintain everything in one place. All of the creatures listed have been bug reported but not fixed. As they are fixed with each update, I'll come back and edit them out.
- Dropping this in to keep the post count right
- Dev comment just to prove they do read this!
Devil Assault - Heroic Hard
First Wave- Fire Bat
- Hell Scorpion (reported as fixed in U26 release notes - not fixed)
- Vermin Keeper (Troll)
Second Wave- Fiendish Troglodyte Archer (fixed in U26 but broken with U28)
- Fiendish Troglodyte Skirmisher (fixed in U26 but broken with U28)
Third Wave
Fiendish Troglodyte Archer (fixed in U26 but broken with U28)- Fiendish Troglodyte Warrior (fixed in U26 but broken with U28)
- Gizhiss (fixed in U26 but broken with U28)
Fourth Wave- Bearded Devil Skirmisher
- Master Stralazar
- Tiefling Sniper
- Tiefling Warlock
Fifth Wave- Bezekira
- Captain Borth
- Orthon
Tiefling Warlock
Devil Assault - Heroic Elite
First Wave- Fiendish Dread Bat
- Infernal Stinger
- Vermin Keeper (Bearded Devil)
Second Wave- Elite Barbazu Shock Trooper
- Fiendish Troglodyte Sniper (fixed in U26 but broken with U28)
- Frenzied Bezekira
Third Wave- Corrupted Fire Elemental
Fiendish Troglodyte Sniper (fixed in U26 but broken with U28)- Hell Fire (reported as fixed in U26 release notes - not fixed)
Fourth Wave- Captain Razor
- Elite Barbazu Captain
- Elite Orthon Shock Trooper
- Tiefling Spellbow
Fifth Wave
Corrupted Fire Elemental- Colonel Yagora
Elite Orthon Shock Trooper- Tiefling Master Warlock
Devil Assault - Epic
First Wave
Fiendish Dread Bat
Vermin Keeper (Bearded Devil)
Second Wave
Frenzied Bezekira
Third Wave
Corrupted Fire Elemental
Hell Fire (reported as fixed in U26 release notes - not fixed)
Fourth Wave
Elite Barbazu Captain
Tiefling Spellbow
Fifth Wave
Corrupted Fire Elemental
Elite Orthon Shock Trooper
Tiefling Master Warlock- Turigulon
Since it's a special case, Devil Assault can be summarised as
Crystal Cove- Azarelle
- Bane Captain Bluebeard
- Bane Captain Jocasta the Plunderer
- Captain Hargo the Hammer
- Dread Captain Arkon the Anvil
- Dread Captain Shipwrecker
- Half-Orc Buccaneer
- Half-Orc Grenadier
- Half-Orc Healer
- Half-Orc Swashbuckler
- Hobgoblin Raider
- Kobold Swabbies
- Pirate Captain Black-Sheep Omaren
- Pirate Captain Parr
- Raider Captain Bloodblade
- Raider Captain Redwing
- Scourge Captain Skyhunter
Anniversary Party- +Eladrin
- +Flimsy Firewood
- +Glin
- +JustBob
- +Niac
- +Rowan
- +Severlin
- +Silorien
- +Steelstar
- +Torc
- Bad Thoughts
- "Dev skeletons"
- Dusty Skeleton
- Fractious Kobold
- Fractious Kobold Shaman
- Fractious Kobold Slinger
- Fractious Ogre
- String Table Error
Night Revels
Delera Graveyard Wilderness Area- Skeletal Archmage *Night Revels* - replaced
- Skeletal Mage *Night Revels* - replaced
Arcane Skeleton *Night Revels*
Aurloc the Pale (Lich) *Night Revels*
Bat *Night Revels*
Doomsphere *Night Revels*
Ghoul *Night Revels*
Minotaur Skeleton *Night Revels*
Minotaur Skeleton Arcanist *Night Revels*
Muckrot (Ghoul) *Night Revels*
Mummy *Night Revels*
Shadow *Night Revels*
Skeletal Archer *Night Revels*
Skeleton *Night Revels*
Wraith *Night Revels*
Zombie *Night Revels*
Eternity Unleashed
Corrupted Guardian (Gargoyle) *Night Revels*
Cultist Ranger (Human) *Night Revels*
Cultist Thug (Human) *Night Revels*
Eternity (Dragon) *Night Revels*
Skeletal Warrior *Night Revels*
Tomb Skeleton *Night Revels*
Getting Ahead in Lordsmarch Palace- Headless Monstrocity *Night Revels*
- Headless Zombie Brute *Night Revels*
Zombie *Night Revels*
Grave Work
Matador Chieftain (Skeleton) *Night Revels*
Matador Shaman (Skeleton) *Night Revels*
Matador Warrior (Skeleton) *Night Revels*
Needle Blight *Night Revels*
Pumpkin Blight *Night Revels*
Spooky Bat *Night Revels*
The Supreme Pumpkin *Night Revels*
Twig Blight *Night Revels*
Haverdashed
Lindilae *Night Revels*
Skeletal Warrior *Night Revels*
Wraith *Night Revels*
Zombie *Night Revels*
Hayweird Foundry- Myereth *Night Revels*
Skeletal Warrior *Night Revels*
Skeleton Archer *Night Revels*
The Kobold's Newest Ringleader
Krylic (Kobold) *Night Revels*
Kylk (Kobold) *Night Revels*
Malkiric (Lich) *Night Revels*
Zombie Kobold *Night Revels*- Zombie Kobold Shaman *Night Revels*
Resurrection Chamber- Bloodthirsty Bat *Night Revels *
- Bone Scavenger Rat *Night Revels*
- Chaney (Werewolf) *Night Revels*
- Lord Harryhausen (Skeleton) *Night Revels*
- Mysterious Stranger (Human) *Night Revels*
Skeletal Archer *Night Revels*- Skeletal Mage *Night Revels*
Skeletal Warrior *Night Revels*- Tormented Ghoul *Night Revels*
- Tormented Shadow *Night Revels*
- Undead Adventurer *Night Revels*
- Werewolf *Night Revels*
The Snitch and the Litch
Ghoul *Night Revels*
Mummy Lord *Night Revels*
Roderic Nettle (Zombie) *Night Revels*
Skeletal Warrior *Night Revels*
Skeleton Archer *Night Revels*
Sneblin (Lich) *Night Revels*
Under New Ravagement
Cerik Thens (Mummy) *Night Revels*
Ghoul *Night Revels*
Mummy *Night Revels*
Vorne (Ghoul) *Night Revels*
Zombie *Night Revels*
Three Barrel Cove Pirates- Ardent Sands Cannoneer (Human) *pirate*
- Ardent Sands Marauder (Human) *pirate*
- Ardent Sands Sailor (Human) *pirate*
- Blood Tide Marine (Human) *pirate*
- Blood Tide Marine (Orc) *pirate*
- Blood Tide Sailor (Human) *pirate*
- Blood Tide Sailor (Hobgoblin) *pirate*
- Blood Tide Windcaller (Gnoll)*pirate*
- Broken Crown Cannoneer (Dwarf) *pirate*
- Broken Crown Sailor (Human) *pirate*
- Broken Crown Sailor (Warforged) *pirate*
- Broken Crown Swashbuckler (Half-elf) *pirate*
- Broken Crown Swashbuckler (Human) *pirate*
- Daask Sailor (Hobgoblin) *pirate*
- Daask Marine (Orc) *pirate*
- Daask Warmage (Gnoll)*pirate*
- Gorgon Cannoneer (Dwarf) *pirate*
- Gorgon Cannoneer (Human) *pirate*
- Gorgon Sailor (Human) * pirate*
- Ill Fate Marine (Orc) *pirate*
- Ill Fate Sailor (Human) *pirate*
- Ill Fate Sailor (Warforged) *pirate*
- Syndicate Cannoneer (Elf) *pirate*
- Syndicate Cannoneer (Human) *pirate*
- Syndicate Sailor (Human) *pirate*
- Syndicate Swashbuckler (Human) *pirate*
- Veiled Chain Marauder (Human) *pirate*
- Veiled Chain Marine (Human) *pirate*
- Veiled Chain Sailor (Human) *pirate*
Aberration- Dead Pykzyl (Doomsphere)
- Drow Scorpion (Scorrow)
- Drow Scorpion Cleric (Scorrow)
- Drow Scorpion Wizard (Scorrow)
- Enrhiikuz (Mindflayer)
- Ganglia (Beholder)
- Garen'thir Szind (Drider)
- Guardian Statue (Drider)
- Watcher of Xy'zzy (Beholder)
- Xig Zit Zarlag (Beholder)
- Yan'thrysis (Drider)
- Zhuggothz (Doomsphere)
- Zoraxzil (Mindflayer)
Animal- Crypt Rat
- Illusionary Lion
- Infernal Bat
- Maddened Bear
- Mountain Lion (Disciples of Shar) (reported as fixed in U26 release notes - not fixed)
- Mrr'dred (Lion)
- Slavering Mist Wolf
- Vargouille
Construct- Castle Sentinel
- Clay Golem
- Crateous
- Hound of Blades
- Iron Golem
- Kudgel
- Roving Flesh Golem
- Stone Guardian
- Stone Scorpion
- Titan Mk II
- Titak Mk III
- Vasilka
- Vulkoor Rattler
Dragon- Barennon
- Dunalenthea *delete*
Elemental- Cascade
- Cloud Spirit
- Elder Earth Elemental
- Greater Fire Elemental
- Gruck
- Magma Brute
- Nodeborn Invisible Stalker
- Rrosp
- Spirit of the Sky
- Strahd's Hate
- Trial Adversary
- Trial Elemental (Air elemental)
Giant- Ahraatz-Ri (Ogre)
- Blackheart Oracle (Ogre)
- Hill Giant Soothsayer (Hill Giant) *FIXED*
- Nar'Azmath (Ogre)
- Ogre Chieftain (Ogre)
- Slave (Troll)
- Stone Giant Scavenger (Hill Giant)
- The Cook (Ogre)
Humanoid- Bandit Dastard (Half-Orc)
- Bandit Scout (Half-Orc)
- Dia Depthcaria (Half-Orc)
- Fiendish Kobold Irregular (fixed - to be confirmed)
- Kobold Maiden
- Paragon Kobold Shaman
- Supply Carrier (Gnoll)
- Supply Carrier (Orc)
- The Receptionist
- Ugg the Assertive
Magical Beast- Svalich Howler
- Tanugash
- Worm Intestine
Monsterous Humanoid- Dominated Servant (Abomination)
Dominated Servant (Disciple of Zehir)- Sahuagin Necromancer
- Yuan-ti Disciple of Zehir
- Yuan-ti Incanter
- Yuan-ti Malison
Misc.- Gelatinous Cube
- Tormented Soul
Outsider- Bahhurat
- Bazdor
- Devil Commander
- Dream Crawler
- Green Abishai Invader
- Harif the Inexorable
- Kriitch
- Ravenous Hezrou
- Shavarath Hezrou
- Tras'ekhan
- White Abishai Invader
Plant- Shambling Doom
- Zuggtmoy
Player Races
Drow- Alakinyon Ken'viir
- Alakraena Xorlarrin
- Asta Jegg Dralnoc
- Cay'Vorym Guard
- Drow Hunter
- Drow Monk
- Drow Shaman
- Drow Wardancer
- Karas
- Master Yeberim
- Mockery Monk
- Prelate Tobias
- Sarnish
- Silent
- Soldiirn Dun'robar
- Teira Szind
- Waeraste Torduis
Dwarf- Duergar Thrall
- Duergar Workers
Elf- Deggum (Half-elf)
- Whomever the Elf Courier
Halfling- Burglar Recruit
- Trapsmith Recruit
Human- Abector of Vol
- Baba Yana (hag)
- Collared Cormyr War Wizard
- Collared Purple Dragon Knight
- Collared Villager
- Cormyrean Magistrate
- Dog Wrangler
- Dragon Knight
- Druid Schemer
- Enforcer Recruit
- Ex-Paladin, Ex-Bard, Ex-Rogue (vampire)
- Galdrinn Fisk
- Karleth
- Netherese Recruiter
- Netherese Summoner
- Nichts Volpe *DUPLICATE - DELETE*
- Poacher (fixed - to be confirmed)
- Prefect Alrrem
- Proud Member
- Shar Worshipper
- Strahd Spawn
- Thug Recruit
- Tidy Lass
- War Wizard
Warforged- Quorforged Minion
Undead
Ghast- Corpse Glutton
- Ghast
- Kabran the Vile
Ghoul- Carrion Feeder
- Wight Chanter
Lich
Mummy
Shadow- Aphotic
- Flamebound Umbral Worg
- Greater Umbral Gargoyle *FIXED*
- Greater Umbral Worg *FIXED*
- Shadow
- Shadow Stalker
- Summoned Shadow (fixed - to be confirmed)
- The Night Whisperer
- Tormented Spirit
- Umbral Gargoyle
- Umbral Worg
Skeleton- Bjorn Heyton
- Fallen Giant
- Kragwulf Heyton
- Madstone Defender
- Starved Prisoner
Wraith- Callie Brennan
- Evrim Whitehair
- Kyle Briarbuck
Zombie- Death Knight (Human)
- Horace Heyton
- Kyleanne Heyton d'Cannith
- Revenant
- Vladimir Horngaard
Vermin- Brown Spider
- Guardian Statue (Spider)
- Rat
- Spider
2nd stage monsters not counted- Acolyte of Flame
- Ahraatz-Ri
- Blighted Magus
- Blighted Friar
- Blighted Soldier
- Blighted Scrapper
- Brimstone Butcher
- Brimstone Impaler
- Brimstone Magister
- Brimstone Friar
- Crooktooth
- Droaam Peacekeeper
- Flamebound Sacrificer (Ghast)
- Flamebound Sacrificer (Skeleton)
- Infernal Warrior (Ghast)
- Infernal Warrior (Skeleton)
- Magician's Assistant
- Manager
Unkillable- Amalgam
- Dedryk Black
- Disciple of Shar
- Drekk
- Enhanced Target Dummy
- Jeets
- Lightbringer
- Lotigath
- Nil
- Nox
- Rand
- Scratchy Cranshaw
- Sor'jek Incanni
- Stormreach Citizen (Elf)
- Stormreach Citizen (Human)
- Succubus Double
- Squall
- Tarvis
- Tormented Soul (killable after quest complete - to be confirmed)
- Vitter
The intention is to use this thread solely to report things that are missing, rather than discussions about the Monster Manual in general.
To list any others, please give the name of the monster, where it's found and ideally what it is being listed as if it's being mis-listed. Please list one creature per post. A screenshot to verify the Name, Type and Race like the others listed would be much preferred to help validate (for example Quorri Stalkers are not spiders and Mudmen are not Earth Elementals).
Note that the forum moderators have been very helpful over the years in deleting entries when requested as they are fixed. If a post is removed it's not for any other reason than it's been fixed!