This is a very good Death Knight FAQ by Elixir of Barthila at WoW Forums. This post helped me answer a lot of general questions while I was leveling my Death Knight.
---------FOREWORD- <3.9> Cataclysm Update
This post has all the basic class information you'll need to start a DK in the post cataclysmic world, including specific information about early specializations, and the new races.
For specialized views into late game DPS/Tanking/Gearing/
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This is an original work (Except for Ghoulgrims list of terminologies... because its awesome)
In this FAQ I will be covering the following areas:
updated
Here we go.
1: The restrictions and such
1a) I bought Cataclysm, and I cant make a Death Knight?!
- As the Death Knight is WoW’s first Hero Class that begins at a high level, there is a level restriction in place to prevent newcomers to the game from missing out on all that Eastern Kingdoms and Kalimdor quest wisdom. You must have a level 55 or over character somewhere on your account to create a Death Knight. This level is set at 55 due to the Death Knight also starting at 55. As Cataclysm is the last expansion in a series of expansions, and the Death Knight was introduced in Wrath of the Lich King, make sure you have a valid Wrath of the Lich King or Cataclysm Level account (checkable under account management).
1b) Awesome, I’m just gonna go roll 9 Death Knight Alts
- You’re welcome to, however I hope you don’t mean on the same realm. There is a restriction on Death Knight creation to 1 per realm. PVP realm rules no longer apply. You can make a Horde DK even if your chars are allied.
1c) What happens to my 55+ character?!
- Nothing. You don’t sacrifice it, it doesn’t become your Death Knight, it doesn’t wave at your Death Knight in a dark alley, etc etc. The Death Knight is created at the character select screen, just like everyone else.
1c-2) What happens if I create a DK with a 55+ char, then delete that char with no other 55+s on my account?
- Nothing. As long as you have a 55+ on creation, your DK will not be affected should you delete all other 55+s.
1d) Role Play Support?
- I'm not a role player, but I can only assume that Role Play rules will still be heavily enforced on Role Play servers. They have strict naming rules too, so don't go namin' your DK Blaumeux or Rivendare :P
1e) So, race restrictions?
- All Races can be Death Knights, Including the Cataclysm races of Goblin and Worgen. NB: If you create a Worgen or Goblin Death Knight you will proceed to do the Death Knight starting area, not Gilneas or Kezan. As such you will be ineligible for realm first of your race
2: General Information on the Death Knight and about the Start of a Death Knight
2a) So, What level does the death knight start as and why is it so?
- The Death Knight starts at level 55. This is due to it being classed as a “Hero Class”. As former heroes of the Alliance or Horde, these corrupted beings have now been raised after death to continue servitude to the Lich King. This does mean when you first create you Death Knight, you’re not officially part of the Alliance or Horde, but part of the Scourge. As seasoned veterans of both life and death, it is believed that running around Goldshire being owned by Defias Bandits is a little below their calibre.
2a.5) I have to go and get my flight paths again?
- You are given every flight point in Eastern Kingdoms except Zul'Aman for some reason. You are given all of them in Kalimdor. As for Outland and Northrend, you're on your own.
2b) 55?! What about all my talents?!
- Upon first creation of a DK, you will have 0 talents. As you progress through the Death Knight only chain, you will get talent points as quest rewards. 1-3 talents a quest. Respecs until you leave the instanced area, are free.