Hero class

A hero class is a character class derived from the base classes, but with exclusive perks. These perks can include a unique starting experience, customization options, resources, class mounts, a higher starting level, and other flavor mechanics. There are currently two hero classes, the death knight and the demon hunter. The concept of a hero class is derived from the "heroes" in Warcraft III.

The term "hero class" is commonly misunderstood to mean that the class is more powerful than other classes. The term instead signifies a unique playstyle and experience, as well as denoting a class of heroes which start at an already "heroic" or "veteran" level, with an experience and gear to match.

Death knight
The first hero class, the death knight was announced at BlizzCon 2007 and was released with Wrath of the Lich King. They start in a unique, phased starting experience set in Acherus: The Ebon Hold. The death knight can be a tank or damage dealer. They do not use shields while tanking, they instead usetwo-handed weapons and heal after losing Health. Death knights also use melee and non-melee magic abilities.

Characteristics

 * Death knights start at level 8.
 * Their resource consists in runic power and runes to power their abilities.
 * Their class mounts are the Acherus Deathcharger and the Winged Steed of the Ebon Blade.
 * Their runeforging ability allows death knights to enchant their weapons.
 * Death knights quickly obtain a full set of gear in their starting area.
 * Because they start the game at such a high level, death knights are automatically given all flight paths for the original continents.
 * It was originally required to already possess at least one level 55 or higher character and to have purchased the Wrath of the Lich King expansion in order to be able to create a death knight. Players were also only able to create one death knight per realm. These restrictions have since been completely removed as of Patch 6.1.

Demon hunter
The second hero class, the demon hunter was announced at gamescom 2015 with the reveal of World of Warcraft: Legion. Their starting experience is set in Mardum, the Shattered Abyss. A leather-wearing melee class, demon hunters fulfill DPS and tanking roles, using flips, dives and agile attacks to evade damage while defeating foes using one-handed weapons and magical abilities.

Characteristics

 * Demon hunters start at level 8.
 * Their resource consists in Fury to power their abilities.
 * Their class mount is the Felsaber.

World of Warcraft
All the hero units of Warcraft III were originally supposed to become hero classes in World of Warcraft. Hero classes were still listed in 2005 on the "Under Development" page of the original website. When a character hit level 40, it could start specializing in skills to become the same kind of hero. However, as Blizzard developed talent trees, they dropped the idea as they believed that the trees would provide enough customization. For example, a night elven warrior could specialize into wielding two one-handed weapons and essentially be a demon hunter, while a dwarven warrior could fulfill the fantasy of a mountain king, or a undead warrior could become a death knight.

It was stated at the time by Nethaera that current plans were to introduce one new hero class per expansion set.

Wrath of the Lich King
Many ideas were considered for the Wrath hero class, which were narrowed down to four front-runners.
 * Death knight
 * Necromancer
 * Runemaster
 * Monk

Runemasters were a type of enchanters who wrote runes on their bodies to give them different physical powers. However, a lot of the features of the runemaster were given to the death knights and, later, the monks. Some of the ideas for the necromancer class were also incorporated into the death knight instead, which was chosen as the hero class. The monk was later added as a regular, non-hero class in Mists of Pandaria.

Bard
The Bard hero class was announced on April 1st, 2008, as a Blizzard hoax.

According to the announcement, the Bard "can vanquish evil with the power of ROCK!" and wields a two-handed "ax" (that is, an electric guitar). Screenshots revealed a new "Fret Bar" interface (resembling that of the  games) powering the Bard's "Groove" resource system. Blizzard claimed that the Wrath of the Lich King expansion would ship with a Frostmourne-themed "guitar-based keyboard peripheral". Two Talent trees were revealed, including Metal Talents (such as Starstruck, Epic Solo, and Axe Specialization), and Punk Rock Talents (such as Shred, Mosh Pit, and Rock 'N Roll Racing).