The majority of these characters were playable at the Heroes of the Storm Blizzcon demo. Some of them were not; screenshots have shown up online of Tyrande and Thrall. Anub’arak, Chen, and Sylvanas have been guessed due to their appearance in promotional art for the game. Zeratul shows up in the Blizzcon Carbot animaton. The rest are from the Adriacraft posted video above.
Diablo
Azmodan
Role: UnknownDifficulty: UnknownFirst Appearance: DiabloSkins: Unknown
Butcher
Role: UnknownDifficulty: UnknownFirst Appearance: DiabloSkins: Unknown
Diablo
Role: Melee WarriorDifficulty: MediumFirst Appearance: DiabloSkins: Kaijo Diablo, Murloc Diablo
Naziba
Role: Ranged SpecialistDifficulty: MediumFirst Appearance: Diablo IIISkins: Female Witch Doctor*, Demonic Witch Doctor*
Skeleton King
Role: UnknownDifficulty: UnknownFirst Appearance: DiabloSkins: Unknown
Sonya
Role: Melee WarriorDifficulty: MediumFirst Appearance: Diablo IIISkins: Male Barbarian*
Tyrael
Role: Melee WarriorDifficulty: MediumFirst Appearance: Diablo IISkins: Demonic Tyrael*
Valla
Role: Ranged AssassinDifficulty: EasyFirst Appearance: Diablo IIISkins: Vampire Hunter Valla
Starcraft
Abathur
Role: Ranged SpecialistDifficulty: Very HardFirst Appearance: Starcraft II: Heart of the SwarmSkins: White Abathur*
Kerrigan
Role: Melee AssassinDifficulty: MediumFirst Apperance: StarcraftSkins: Succubus Kerrigan
Nova
Role: Ranged AssassinDifficulty: MediumFirst Appearance: Starcraft: GhostSkins: Roller Derby Nova, White Armor Nova*, Eldar Nova*
Raynor
Role: Ranged AssassinDifficulty: EasyFirst Appearance: StarcraftSkins: American Raynor
Siege Tank*
Role: UnknownDifficulty: UnknownFirst Appearance: StarcraftSkins: Unknown
Tassadar
Role: Ranged SupportDifficulty: Very HardFirst Appearance: StarcraftSkins: Mecha Tassadar
Tychus Findlay
Role: UnknownDifficulty: UnknownFirst Appearance: Starcraft II: Wings of LibertySkins: Zerg Tychus*
Zagara
Role: UnknownDifficulty: UnknownFirst Appearance: Starcraft II: Heart of the SwarmSkins: Unknown
Zeratul
Role: UnknownDifficulty: UnknownFirst Appearance: StarcraftSkins: Samurai Zeratul*
Warcraft
Anub’arak
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: The Frozen ThroneSkins: Red Anub’arak*
Arthas
Role: Melee WarriorDifficulty: MediumFirst Appearance: Warcraft III: Reign of ChaosSkins: Prince Arthas, Death Knight Armor Arthas*
Chen Stormstout
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: The Frozen ThroneSkins: Unknown
Cho’Gall
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft II: Tides of DarknessSkins: Unknown
Elite Tauren Chieftain
Role: Melee WarriorDifficulty: MediumFirst Appearance: Warcraft III: the Frozen Throne (credit song)Skins: Glam ETC
Faerie Dragon*
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosSkins: Unknown
Falstad
Role: Ranged AssassinDifficulty: HardFirst Appearance: World of Warcraft (book character prior to)Skins: Dark Iron Falstad
Gazlowe
Role: Melee SpecialistDifficulty: MediumFirst Appearance: Warcraft III: the Frozen ThroneSkins: Camo Gazlowe
Gnomish Flying Machine*
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft II: Tides of DarknessSkins: Unknown
Illidan
Role: Melee AssassinDifficulty: Very HardFirst Appearance: Warcraft III: Reign of ChaosSkins: Blood Elf Illidan
Jaina
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosSkins: Purple Jaina*
Malfurion
Role: Ranged SupportDifficulty: EasyFirst Appearance: Warcraft III: Reign of ChaosSkins: Brown Robes Malfurion*
Muradin
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosSkins: Magni Muradin*
Rexxar
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: the Frozen ThroneSkins: Unknown
Stitches
Role: Melee WarriorDifficulty: MediumFirst Appearance: World of WarcraftSkins: Psycho Stitches, Space Marine Stitches*, Zerg Stitches*, Warlock Set Stitches*, Butcher Stitches*
Sylvanas
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosDifficulty: Unknown
Thrall
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosSkins: Unknown
Tyrande
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft III: Reign of ChaosSkins: Unknown
Uther
Role: Melee SupportDifficulty: EasyFirst Appearance: Warcraft II: Tides of DarknessSkins: Judgment Uther, Space Marine Medic Uther*, Lumberjack Uther
Zul’jin
Role: UnknownDifficulty: UnknownFirst Appearance: Warcraft II: Tides of DarknessSkins: Unknown
An asterisk (*) near a Heroes of the Storm character name or skin title is given when it is not known currently. Tyrande image taken from here.
Speculation
This list is on the official Heroes of the Storm site. It has so many more characters; some are familiar to me and some are not. It’s hard to tell if most of these will become characters or not, but it is safe to bet that a few will.
Lost Vikings’ Baelog and Blackthorne’s Kyle are seen in this Heroes of the Storm image.
Warcraft’s Garrosh, Deathwing Genn Greymane, Gallywix, Wrathion, Kel’Thuzad, and more are all present. There are many representatives from Diablo, including Deckard Cain and some from Starcraft, as well.
Some of these characters are probably safe to rule out as not making it into Heroes of the Storm, like the hex frog.
Want to see more Heroes of the Storm? This list will be updated often so be sure to come back.