The big news about Blizzard’s new World of Warcraft expansion Wrath of the Lich King has been the addition of the game’s first Hero class, the Death Knight. But, as WoW lead designer Tom Chilton explained today, creating a specialized class that was both unique and balanced was a huge challenge for the team. To recap, the Death Knight class will be an unlockable character that an avatar of any race can attain through a series of level 80 quests. Starting off at a high level, the Death Knight will fulfill the role of both a tank and a damage-dealer, using its plate armor, bladed weapons, and deadly spells to wreck havoc.

The class will feature a new resource system based around three schools of runes, which are added outside of combat to the Death Knight’s weapons. Players will consume the blood, frost, or unholy runes to cast spells or use abilities during combat–although the runes are based on a cooldown system, so timing will come into play.

“We felt like there was room for the addition of another tanking class,” Chilton said about the Death Knight, mentioning that he still sees groups that frequently lack tanking classes. In a talk on the evolution of character classes, Chilton revealed that the team has always had plenty of ideas for implementing hero classes, but that not all of them would have worked.

For instance, one plan was to simply “fork” each class, much in the same way that talent trees branch out. Ultimately that would have been a dangerous move, as Chilton explained that a doubling or tripling of character classes could have thrown the entire game out of balance.

Another idea was a “character morphing” system, where the player would simply convert his existing character into the Death Knight class. Chilton noted that this ultimately would have been an awkward process, as players would be to choose between parting with their original class or being left out of the Death Knight fun.

These problems lead the team to eventually settle on the current multi-character system. Before moving on to the balance of existing classes, Chilton said that the Death Knight characters will have full talent trees, and will begin at their high level with points to burn.

After a slide displayed a list of originally-planned classes that didn’t make the cut, such as the Blademaster and Demon Hunter, Chilton remarked that the Death Knight was on that list at the last BlizzCon. The class has since, for obvious reasons, been taken off, and Chilton coyly remarked that the remaining two classes might follow suit in the future.

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