This guide is a short excerpt from http://www.wowtalentspecs.com/Bestblooddeathknightpvpguide.html :
Let me start by saying that I have a lot of experience in world of warcraft and considered myself one of the best in stormstrike until I retired a few months ago. I play every now and then just for kicks but devote most of my time sharing tips and tricks with others. I have played every class at 80 and know probably every trick there is to know. You don't need the best gear, or enchants, and epic gems to win. You just need to be calm, and follow my guide.

As a blood death knight there are some classes you love to see running by themselves, and there are some that you avoid. All death knights hate two things, Shamans and other Death Knights. You probably hate fighting other death knights the most, but after this, maybe you will have a change in heart.

First of all let me recommend a deep blood build with dancing rune weapon and dip into frost for lichborne and annihilation. If you need specific builds, go to my website www.wowtalentspecs.com . This guide is based on a build similar to this with rune tap, hysteria, vampiric blood, lichborne, and dancing rune weapon. You also need to learn to key bind if you are not already. This is a huge help and cuts down on the time your eyes are off the enemy.

I will go through a lot of different scenarios with you. Along the way I will throw in some tips you may have never saw before and some strategies that I know you have never used.

A very well played shadow priest can be a pain. They will be healing for about 25% of all damage they do and they will have great burst. They will not be able to heal, but mind flay and mind blast will be easy targets to mind freeze. Make sure you mind freeze every mind flay. This will make them manually refresh SW:P. You want to fight this one in blood presence.

Psychic horror will be your bane if you are not careful. You will approach this fight with caution. This is one fight you will start with death grip. Right when you death grip you want to silence the priest while he is in the air.

You want to pop your DRW macro now. Do not wait for one rotation. You want to pop your AMS right as the silence wears off.

The reason you are trying to lock down the priest while bursting is that he can easily psychic horror, silence, fear, and kite you to death. Really good shadow priest are hard to kill if they take control of the fight. If you are feared before you can start the battle, trinket or lichborne out of it and continue where you left off.

You want to OB,OB,HS,HS while DRW is up. This will give you 6 seconds of uninterrupted burst. This will force the shadow priest to dispersion and you can wait to unload again.

You should still have your lichborne and trinket. When the priest comes out of dispersion, you want to blow lichborne and make the priest blow psychic horror to disarm you. You will just have to eat this one and IBF thru the damage. You can still DC and IT. Use these two and mind freeze while disarmed. You can also rune tap at this time if you need to.

Now that lichborne is gone and psychic horror is gone, the priest will try to fear. All you have to do is trinket out of this and finish the fight.

The main thing you need to concentrate on in the fight is to get the jump and get 6 seconds of damage off with DRW. You also want to make sure you control casts with mind freeze. This will get you in control of the tempo and all you have to do from there is stay in control.

This can prove to be a challenge if you are not in control from the beginning. You need to use trinket and DG to regain the fight fast. If you chain silence and AMS together you will be immune for a few seconds and let you get the needed damage off.

If they switch out of shadow for they will be healing. Make sure you mind freeze and finish the fight here because this is an act of desperation. You should have no problem with kiting, but if you run into this simply use a 5 second COI rotation.

-Brandon C. ; Aka. darksun22