I tried out Unholy in ICC this past week. I was really impressed with the results. Keep in mind that my 2-hander is pretty crappy. Despite having the worst 2-hander in the guild, I was still very competitive on dps, hitting as high as #2 on bosses.

To raid, I chose a heavy AoE build which favors multi-targetting over single-target damage. I expected it to fare well on trash, but not so well on bosses. My previous DW-Frost build did exactly the opposite. My hope was that this spec would make me at least competitive with the consecrate-batteries on the trash packs.

You will notice that this build does not take Reaping, so you will not get Death Runes. At this point, especially with lower gear level (I don’t really have much from ICC) Reaping is not recommended.

Strengths
High, Sustained AoE Damage, the highest possible for a Death Knight, doesn’t rely on procs.
Raid Utility – Ebon Plague provides great raid utility and a nearly unduplicated raid buff.
Perma-Ghoul, Bone Shield – Enhanced survivability and damage

Weaknesses
This spec suffers some in Single-target dps. While competitive, it won’t get you the highest possible numbers because the spec is geared specifically toward AoE damage. It might be a good idea to set a decent single-target spec as your alternate spec.

17/0/54 Rotation

Multiple Target AoE – Opening Rotation ONLY
     

Rotation 1
    Dump(   )

Rotation 2
    

Single Target

Rotation 1
       

Rotation 2
    Dump(   )

Glyphs

Glyph of Disease
Glyph of Icy Touch
Glyph of Death and Decay

Stat Weights

Stat weights are how you compare the benefit of one stat over another for a given spec. Stat weights are different from spec to spec, so if you are not unholy, these stat weights will not apply to you and will be different for your spec. So after getting 8% melee hit (also called "Hit Capped") your best stats are Strength > Crit Rating > Armor Penetration. Strength has a stat weight of 3.02, while Armor Pen has a stat weight of 2.01. This means that Strength is just about 50% better for you, per point than Armor Pen. For a more detailed explanation of how to work with stat weights, please see my BiS (Best in Slot) post.

Please be aware that as you start getting more ICC gear especially Tier 10 Armor Pen starts to scale more than Crit Rating. Keep this in mind as you get better gear from Icecrown Citadel.

The current stat weights for Unholy are:


WeaponDPS: 6.67
MeleeHit (<8%): 3.62
Strength: 3.06
Crit Rating: 2.16
ArP Rating: 2.01
Haste Rating: 1.75
Expertise Rating: 1.63
Agility: 1.55
Attack Power: 1
Armor: 0.028

Stat Weights via ElitistJerks