World of WarCraft's first Hero Class is a plate-wearing tank/DPS hybrid that works a little something like this: When players hit level 80, they'll be able to embark on a quest (similar in difficulty to the Warlock's epic mount quest, back before the level cap was raised to 70) that unlocks the ability to create a Death Knight character. The Death Knight starts at a high level (somewhere around 60 or 70, though Blizzard isn't certain yet), so you won't have to grind your way back up all over again. It's intended as an alternative, advanced class for end-game use only.
Rather than using rage, energy, or mana, Death Knights have a special "rune sword" displayed beneath their health bar, onto which the player can etch six different runes (choose between Frost, Blood, and Unholy). Different abilities require different mixes of runes, and using abilities consumes the requisite runes until a cooldown timer causes them to be available again. Stuff like talents, spells, and other specifics are still being finalized. So are key questions like what races can be a Death Knight (start a Gnome petition now) and whether unlocking the Hero Class on one server means you can create a Death Knight on any server.
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Information About the Death Knight Warcraft News
Blizzard wanted to get this information out about the Death Knight, check it out...
There are a lot of things still being worked out with the Death Knight class such as specific spell abilities. Unlike a traditional caster type however, a Death Knight's spell power comes from runes that are etched into their blade. Think Warcraft III when you think about the possibilities of abilities for the Death Knight. I say possibilities because things are still in process for the development of the class and there will be (of course) a lot of testing for balance done. Given that this is our first Hero class we're unveiling, you can be sure we're going for the coolest of the cool for this class.
Runes and Mana pool
The runes they inscribe on their weapons are their mana pool (of a sort). As they use their abilities, the runes will be exhausted. After a period of time the runes will refresh. So, they don't have a traditional type of mana pool. You'll most likely see some screenshots of it, but the Death Knight (at current) has three different types of runes that they can inscribe on their weapon: Blood, Frost, and Unholy. Runes can only be inscribed out of combat ( all of this is subject to change as development continues.)
The rune types don't dictate a new damage type, they're simply a resource that spells and abilities will use when you activate them. The spells and abilities won't necessarily be "blood, unholy, or frost" damage.
Imagine it being three different energy pools which you can change the size of before you get into combat.
About weapons
There's no final decision or announcement on how multiple weapons would be etched, or how weapon switching may affect the etched runes. What has been discussed to some degree is that the main-hand weapon would be etched and that's it, but it's too early to say what would be allowed in the final game.
Which level?
Also, we haven't decided on what level you will start as your Death Knight, but it seems that it should be easy enough for someone who has levelled a character to level 80 and done the quest to be able to adapt to a Death Knight fairly well. It's not quite the same as handing it over to someone who is still learning the game. There are lots of opportunities for someone to solo and group to learn how to play the class.
Which race?
It's true that the current plan has been heavily discussed to go ahead with all races, but no final decision has been made. After talking to Chris he wasn't totally sold on the idea. Both are technically correct in that the current plan of some of the developers is to go ahead with all races, there's been no final decision made and no real work has progressed to force a decision just yet. The FAQ is more accurate at this time, in my opinion.
Lore-wise there's really no reason why a specific race couldn't become a Death Knight.
All races can be challenged mentally and physically, their will dulled, and be cast down into madness ... and darkness. Their souls drawn into the runeblade they wield.
Compared to other classes
They are not planned to be more powerful, them being a hero class simply means they're introduced at a higher level, and in general will reference the more powerful hero types of Warcraft history.
It's our intention to integrate them into the current classes, balance them appropriately, and have them provide an additional - but equal - role in groups and raids as compared to other classes.
Will there be other hero classes?
Yeah, well that kind figures in to the new definition of what a hero class is. It allows us to add new classes that start at higher levels, keeping players relatively kept up as we continue to release expansions and raise the level cap, and ultimately it really fits to use the heroes from past Warcraft games as inspiration. Some other hero classes could definitely be things like Demon Hunter, Blademaster, etc.
http://wowvault.ign.com/
More info from the Devs:
Moving onto the Death Knight, which will be the first hero class, it is expected to be able to fill a tank & DPS role. It will have the ability to tank with a two-hander or while dual-wielding (Tom Chilton then commented that you never saw Arthas wielding a shield). The class will be able to wield plate armor and will have a nice mix of spells & abilities which will be a mixture of casting & melee. Being the first hero class there were many questions that were in peoples minds that Tom answered fairly well.
Being the first hero class it will be an unlocked class, meaning a quest chain of some time (think of the Warlock Epic Mount questline), which after that you can create a Death Knight (any race) that will start at a relatively high level (assumedly 55-70 at this point), and this will also allow the ability to unlock more hero classes which are suppose to be down the pipeline. Alliance and Horde alike will be able to use the Death Knight.
The combat system for the Death Knight is very unique to itself and there is a rune resource system. You will be able to cast using three unique rune school of magic: blood, frost, and unholy. You can restore these runes and carve them into your weapons out of combat. Rune cooldowns can be affected by talents and attributes. Certain spells can also activate runes and spells can consume more that one rune. Shown there were only six slots to use for the runes. The Death Knight class unfortunately was not playable at the show, but it looks like it will be a very unique class, it will just be interesting to see how they balance it with the nine classes currently in the game.
http://wow.stratics.com/#23918