The Death Knight is the first hero class in World of Warcraft; once certain criteria are met, you will unlock the ability to create a new Death Knight character, which will begin play at a high experience level.

Death Knight Powerleveling 55-80!
If you want to create a Death Knight in World of Warcraft, you must to level your character up to 55 at least and complete 41 quests in the Death Knight's starting area. To save you time, we'd like to help you with the service Unlocking Death Knight WotLK: Death Knight quests chain...
Note: The "time"  in form below is just estimated duration, please do not worry about exceed time occurrs in your powerleveling, we will continue the leveling until complete it without extra charges!