Long before the two sets of Alliance Knights, the Scarlet Crusade and the Argent Dawn, took up arms against each other, humanity had one legion of Knights who worked to keep humans safe. Lord Alexandros Mograine was part of a charge against the horde, and wound up with a strange black artifact- one that hurt his hand, giving him wounds that would not heal and drained his paladin powers.
This crystal was dark, the antithesis of the light that the Paladins embodied, and Mograine kept it hidden amongst his possessions until rumors of the scourge were heard in Lordaeron. Then, he revealed it and told the rest of the council that if they could find the antithesis of the crystal of darkness, it could be used as a weapon against the scourge. The others weren't happy to hear that and tried to destroy the crystal with holy spells, which transformed the dark crystal into the one of light that Alexandros had been talking of.
This crystal was forged into a sword, known as Ashbringer, that had the power to reduce Undead of the Scourge into a pile of Ash and was wielded by Alexandros himself. But the coming of this... scourge of the Scourge didn't go unnoticed by those in charge of the Scourge, and they set out to rip it from Alexandros themselves. So they planted a Scourge in one of Alexandros's knights, who worked on his son, Renault, who had always been treated as the lesser of Alexandros's two sons.
Eventually, Renault killed his father with Ashbringer, leading to the sword's corruption, and the breaking of the Paladins and Knights into two sects: The Scarlet Crusade, and The Argent Dawn. The Scarlet Crusade is fiercely human-only, where the Argent Dawn allows non-humans in their ranks.
Alexandros's other son, Darion, fought his way into the Scourge stronghold to try and rescue his father, unaware that he had already become a deathknight. But to free his father's spirit from the corrupted remains of Ashbringer will require as great a sacrifice of love. Can Darion make that sacrifice, and what will the ending of that sacrifice be?
I read this knowing nothing about the story of World of Warcraft, nor of how central the coming of Ashbringer was to the early game. But here we have it, told not as backstory, but as the main story. You can read in WoW that Renault Mograine killed his father- and here you can see why- it wasn't some dark whim, but a foul plot with a Scourge working on him, pointing out how his father didn't treat him well compared to Darion, and how unfair that was.
We also get to find out why- Renault reminded Alexandros of himself, while Darion reminded him of his dead wife. It doesn't excuse him, of course, but it does make it somewhat understandable. None of which mattered to Renault, because it left him feeling that he couldn't do anything right for his father.
The ending of the comic is even sadder- the outcome of the entire story is just very, very sad, and you get the feeling that there is little that can be done to make it better. But, given that so much of this story is already set out in the backstory and quests of World of Warcraft, there is no real reason to buy this comic unless you are a crazy-mad completist, as you probably already know what happened or will happen. And those who aren't into WoW, like me, will wonder who all these characters are. Suffice to say, save your money. It tells an interesting story, but I don't see why anyone should care.