13,394 NPCs

Classic reference; current Forever availability is unconfirmed.

NPCLevelTitleZone
Undead Nerubian60–61
Frost Spectre41
Idol Room Spawner1
Ozzie26
Mithril Dragonling60
Infernal Servant55
Hukku's Voidwalker52
Hukku's Succubus52
Hukku's Imp52
Splinterbone Elite43–44
Felhound Tracker1
World Gnome Engineering Trainer10Gnome Engineering Trainer
World Goblin Engineering Trainer10Goblin Engineering Trainer
Massive Infernal63
Forest Creeper50–51
Emerald Dragon Whelp55
Seinrick Coulthane35Skinning Trainer
Swimming Murloc Test1
Battle Chicken1
Sandfury Acolyte42–44
Mechastrider1–2
Paladin 20 AlternateHighDamage20
Pet Bomb1
Blackrock Drake51
Riding Horse (Warhorse)1
Burning Spirit30
World Event Generator5
Farm Chicken1
Launcher1
Launcher21
Enraged Wyvern55
Sleeping Dragon60
Spawn of Bael'Gar49–50
Horde Defender18
Horde Axe Thrower16
Gorishi Egg50–51
Gorishi Grub48
Enraged Felbat55
Enraged Gryphon55
Enraged Hippogryph55

Classic reference data from QuestieDB (Forever data, commit c5de61a), with positions on Forever's zone maps. It doesn't confirm that an NPC, location, quest or item is in Forever.