Information as of 5.0.4 (pre-Mop patch, level 85)
What kind of talent decisions need to be made?
You could not choose talents and do just fine in non-heroic content. Your talent choices make your Death Knight play differently, but they do not make your Death Knight work.
If you are overwhelmed with buttons already, I recommend going for passive talent choices: Roiling Blood, Purgatory, Death's Advance, Runic Corruption.
How do I properly enter a fight?
You have a few important jobs:
- Keep the mobs (particularly melee mobs) off the healer. Do this by establishing at least 1 point of damage on all mobs. BloodBoil/HeartStrike/DeathAndDecay are the tools for this.
- Provide the dps with a safe target. Mark it with Skull (I have skull on my middle mouse button. Hit that target with DeathStrike (a high burst damage ability).
- Survive - this might mean getting diseases (ScarletFever) up if you expect the fight to last more than 10 seconds. This might mean using a defensive cooldown to protect yourself from the full alpha strike of the pack. This might mean interrupting a spell.
- Gather the mobs for AOE opportunities. You may need to death grip (or use line of sight) to move a caster. If there are two casters, pull one to the other.
- Call for crowd control if there is some mob you don't want to tank or interrupt. Mark the CC target with Moon. Wait for someone to put it to sleep.
Finishing a fight: Once you've established enough threat that no mob will break from the pack, and you know you'll survive the incoming damage... you might want to conserve Runic Power for the next fight.
What sorts of ability rotations/priorities should I use?
Understand global cooldowns. Most abilities cause a global cooldown (gcd), which prevents you from using other abilities immediately. This is why you can't put out 2 DeathStrikes in the same second, they must be spaced. You can, however, use a DeathStrike and a BoneShield in the same second, since BoneShield is off the global cooldown.
Also understand Rune Recharging...
Suppose you HeartStrike twice in a row (2 blood runes). The first HS will cause your first blood rune to start to recharge. The second HS will consume the second blood rune, but that rune won't start to recharge until the first blood rune has completed its recharge. My Rune recharge speed is 8.33 seconds (shown in the character stats screen under melee). This means, I will have to wait ~16 seconds for that second blood rune to recharge.
You always want each flavor of Rune to be recharging (otherwise you are wasting the recharge). But you don't want to just spend all your runes and stand around.
I recommend DeathStrike -> HeartStrike -> RuneStrike -> something else -> repeat.
Something else can be Horn of Winter, Outbreak, a second RuneStrike if Runic Power permits, or a free BloodBoil. Or Something else can also be occasionally skipped, as you do have a second set of runes, or Runic Conversion may kick in and give you your runes back early.
If you truly get stuck without Runes, that's what EmpowerRunicWeapon is for.
What procs do I look out for?
Will of the Necropolis (big central indicator) : If your health gets low, you get to use a free Rune Tap
Crimson Scourge (bubbly side indicators) : melee attacks against diseased targets occasionally grant a free BloodBoil or DeathAndDecay. Those free BloodBoils are great for keeping your diseases up, thanks to ScarletFever.
What glyphs are useful?
I don't view any glyphs as critical for tanking 5-man normal. Maybe Glyph of DeathGrip, to be sure you're in range. If you're powering through groups quicky, Glyph of Outbreak might be good (you carry runic power from the previous fight).
What are the differences between tanking lots of mobs and tanking just 1 boss? What tools can I use if things go wrong, like a ranged DPS pulls aggro or adds show up?
Target switching. In a pack, a mob may break for the dps if they don't target your skull-marked safe target. You'll need to switch target to use DarkCommand/DeathGrip or some attack to get that mob back.
What other questions should I be asking?
- Hit and Expertise are fine - use the tooltip to see if you need more to avoid missing.
- Parry and Dodge are tank stats - don't be shy about getting those.
- Haste, this lowers your Global Cooldown and Rune Generation speed. More abilities is a good thing.
- Crit - doesn't really matter.
Addons... Go get TidyPlates. This will help with the target switching problem.
In the rotation question above, I talked a lot about threat building abilities. Here's a list of non-threat building abilities that you should be familiar with. All of these abilities cost no runes and are off the global cooldown, unless noted.
Defensive Cooldowns - Bone Shield, Rune Tap (1 Blood Rune), Icebound Fortitude, Anti-Magic Shield, Vampiric Blood, Dancing Rune Weapon (60 Runic Power)
Interrupts - Strangulate (Global Cooldown), Mind Freeze
Taunts - Dark Command, Death Grip
Resource Generator - Horn of Winter (Global Cooldown), EmpowerRunicWeapon
Think about positioning and facing - dragon breath goes forward, you don't want it on your group. Parry only works against attacks coming from your front.
Keep HornOfWinter and BoneShield up at all times.
Watch out for patrols (everywhere) - also Runners (if you're starting with Outlands dungeons).