Well i will add: in WC3 DKs are draining life from their own ally to regain their HP. So Blood talent tree would be some kind of Healing and DPS or more like warrior strikes. Maybe the blood talent tree will have some enchant on wepon on hit or bleeding , consuming shadow dmg some kind of warr/lock type of DPS. This are just ideas in my  mind according to WC3 and blizz type of creating classes and their spells. Frost, according to me would be something like cold death or freezing strikes or something like that. It may be some kind of cold shadow spells. Unholy according to me would be anti paladin or the dark side of the paladin. Maybe the DK will have some nice aura like Unholy Aura (AOE dmg) or use shdow spells to heal himslef and dealing alot of direct DMG. I am interested about what kind of source he will use to cast his spells. It may be some kind of unholy energy , shadow power, or just mana.
Well i can asure u that it will be very interesting and the thing that i am curious about is how he will combine with other classes for raid or PvP , which are his weak spots and strong as well.

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