While what shark suggested is a good start there are a lot of other things to consider for unholy pvp.
Including but not limited to:
micro-managing timmy (using uber-timmy for burst and binding his stun for pressure/kills)
Keeping the DC debuff on the target (I'm assuming that still exists but I haven't checked in a while)
Make a concious decision for SS/NS (2's/3's with no healer often makes stacking NS to the sky a bit of a waste - unless you're fighting a warrior )
Utilising your final tier talents - DG for fear bomb teams etc.
For maximum damage what's listed above is a start but there are a lot of factors to consider and you won't often find yourself just sitting on someone without being bothered unless you're in a random bg.
There is no "rotation" in pvp, and especially not for Unholy DKS. Remember that we go somehow like this from start to end: DoT class (applying DoT's) > Melee class (Scourge/Festering) > Caster class (Death Coil) > Pet class (5xstacks Shadow Infusion). We start of as a DoT class with applying DoT's, then we go over to a Melee class with some strikes, then we take the role of a caster with Death Coils and kiting, and after we get 5 stacks of Shadow Infusion we take the role of a pet class.
Its what I love about Unholy DK's, we got some of everything in us.
But your priorities will be to get on both diseases, blood boil/festering strike to spread aids and get death runes.
Death Runes: Necrotic
Unholy Runes: Scourge
Blood/Frost: Festering/Blood Boil
You should have your pet abilites binded, atleast Leap and Gnaw, and turn off auto.
Should have Blood Tap talent, so you can choose yourself when you want deathrunes for Necrotic to put max pressure up
And yea, USE SOUL REAPER when you want to land a kill, people underestimate this spell.
Also, in 5.2 you will apply bots diseases from Plague Strike.
Last edited by Machomaije; 2013-02-16 at 07:38 PM.
on top of what people said, i'll suggest : https://www.youtube.com/watch?v=sWQCe3oV76I
written by a glad DK and i must say one of the only UH one out there that tries to give faith into this spec and plays it no matter what people say.
Dunno if people are forgetting about IT being on reaping, but BBx2 and ITx2 will be pretty good next patch too, it may do less damage but has the benefit of spreading DoTs (with RB, which is generally the best talent that tier) to anything in range (a primary way of causing pressure as Unholy) and possibly dispelling important HoTs/shields which need to be reapplied, wasting globals from healers and draining excess mana.
Generally plague strike can function as a pseudo (single target) desecration with Chilblains too as it will apply an 8 second slow, meaning you can preserve your Death Rune setup but still be able to keep your grip on a target.
Obviously not advocating people to spam BB IT and PS, but there is no "set" rotation even if people are leaving you alone because there may be times when IT+BB is better and others when FS is better.