The story of Darion is inextricably linked to that of his father, Alexandros Mograine. His Father was a paladin of the Silver Hand, under the leadership of Uther Lightbringer. Alexandros was a very powerful fighter and had earned the nickname Ashbringer for the way he and his sword, of the same name, cut down the scourge, turning their bodies to ash. His sword is actually a very special sword, able to channel the light itself through an enormous gem in the blade, to increase the power of the wielder and do devastating amounts of damage to undead enemies.
Along with Darion, Alexandros had another son, the elder of the two, Renault.
Renault did not follow his father into the Silver Hand, instead he joined the Scarlet Crusade. This organization was filled with fanatics who despised the scourge with such passion that they would do anything to wipe them all off the face of the earth. Sounds pretty harmless right? No one needs the scourge. The problem lay in their leadership. Early on, one of the high ranking members of The Scarlet Crusade had been killed and his body taken over by a demon named Balnazzar, so the true purpose of the crusade became to prepare Azeroth for the Burning Legion.
Balnazzar was sent to oppose the scourge because Arthas had turned against the Burning Legion and was acting in his own interests. So the crusade was used to fight the scourge but it was also used to dismantle any powerful threats that the Demon decided would get in the way. Alexandros, or Ashbringer as he was more commonly called, became one such threat.
Renault was welcomed into the Scarlet Crusade with open arms and Balnazzar started to work on him, preying on his need for approval and recognition, until he convinced him to betray his father. With promises that he would be promoted and attain a high rank within the organization, he lured his father and High Inquisitor Fairbanks into Stratholme where they were ambushed by thousands of scourge.
Ashbringer was magnificent, swinging his blade with tireless ferocity, he decimated the undead, ash falling wherever the blade met flesh. But even his indomitable spirit began to tire, and although he left the dead piled high in heaps all around him, eventually Ashbringer fell from his fingers, too exhausted to grip the sword. This is when Renault snuck forward, grasping his father's sword he stabbed him in the back and then fled.
This is where High Inquisitor Fairbanks comes into the story. When they were surrounded by the scourge he hid under the bodies of the dead in order to survive and so witnessed the entire thing. When it was all over he made his way back to the Scarlet Crusade and tried to tell everyone of Renault’s treachery. It was claimed that he had been tainted by the undead and he was executed. This decision did convince some of the members that their order was not what it once was and they left to form their own group, the Argent Dawn.
Alexandros’ body and his sword were taken by Kel’thuzad to his fortress Naxxramas where the lich raised him up as a Death Knight and set him as the leader of The Four Horsemen.
Back to Darion. Not knowing the circumstances that caused his father’s death Darion simply thought he had perished battling the scourge and was terribly sad. Wanting to follow in his father’s footsteps he joined the Argent Dawn and became a paladin of the holy light. Attacking the Lich King’s forces he was eventually sent to the floating fortress of Naxxramas where he and his party did battle against the Four Horsemen. They took heavy losses but eventually defeated the horsemen and Darion, (not knowing he had defeated his own father) carried away the Ashbringer, although it was now dark and corrupted as a result of his father’s murder.
Strangely Darion began to hear faint whispers from the sword and, listening to them, he was lead to the headquarters of The Scarlet Crusade where he went to see his brother. At first Renault thought that Darion had decided to join the Crusade and was happy to see him, but when he glimpsed the Ashbringer on his back Renault fell into a furious rage and attacked him. He saw Darion as a last link to his treacherous past, come to torture him.
At this, Alexandros Mograine rose up out of the sword as a vengeful spirit and confronted his son. Terrified, Renault fell to knees and begged for forgiveness. Immediately Alexandros beheaded him and then spoke the words “I forgive you” before returning to the sword.
Realizing that his father’s soul was trapped within Ashbringer, Darion set about looking for a way to free him. The spirit of Fairbanks appears to Darion in a dream, and tells him to seek out Tirion Fordring.
At this time in his life Tirion has just been banished, his son is dead, (long story for another time) and he is very bitter. After hearing Darion’s story he tells him that nothing can be done for him. It is hopeless. Refusing to give in to despair, Darion exhorts Tirion to be a hero again and come back to the crusade but Tirion is unmoved. Finally as Darion makes to leave Tirion gives him a little hope. “Maybe, an act of love, greater than the act of evil will free your father’s soul”.
With only those cryptic words to guide him Darion goes back to the Argent Crusade and joins the contingent guarding Light's Hope Chapel. The leader there, Maxwell Tyrosus, explains to him that thousands of brave knights that died fighting Arthas lay buried beneath the chapel. It is a Holy place that must not fall to the scourge, or all light may be extinguished.
When the forces of the scourge attack, the Argent Dawn is hard pressed and it looks bad until Tirion shows up to help, it’s possible his meeting with Darion was what he needed to pull him out of his depression and join the fight again.
Just when it looked like the forces of the Light may have saved the day, Kel’Thuzad joins the scourge forces. Learning that The Lich King’s Right Hand has joined the battle, Darion immediately rides out to meet him, wielding Ashbringer just as his father once did. But that is not enough, Kel'thuzad is not afraid, and in a moment of clarity Darion realizes what he must do. As an act of love, not only for his father, but also for the cause he believes in, Darion plunges Ashbringer through his heart with the words "I love you, dad."
In response to his noble action, the souls of a thousand vengeful knights erupt in pillars of light that purge the hills around the chapel of all traces of the Scourge. All that remains are the figures of Kel'Thuzad and the undead figure of Darion Mograine, the Corrupted Ashbringer still pierced through his chest. Because of course Kel'thuzad is going to take this opportunity to make a new Horseman to replace the one he lost.
So Light’s Hope Chapel was saved and Alexandros’ soul was freed, but Darion was lost. He became the leader of the Death Knights of Acherus, and led the Lich King’s forces in the Plaguelands, defeating the Scarlet Crusade forces there and culminating in a final battle at, you guessed it, Light’s Hope Chapel.
This time on the opposing side Darion learned that Ashbringer would not strike against the forces of the light, it refused to obey him and, overwhelmed by the power of the consecrated ground, he was forced to kneel and surrender to non other than Tirion Fordring himself, now leader of the Argent Crusade. (made up of the combined forces of the Silver Hand and the Argent Dawn).
Tirion rebukes Darion for becoming the antithesis of everything he used to fight for, and as he kneels in defeat he looks up to see a spirit walk out of Light’s Hope and approach him. It is his father, Alexandros Mograine. As Darion watches, the small form of a child walks out of his chest to meet his father and he sees himself as a boy, reenacting a scene from his childhood.
His Father is going off to fight and he wants to go with him but Alexandros says he is too young, and he would never forgive himself if Darion was to be hurt. The child responds that he would not care if he died, as long as he could be by his father’s side, and fight with the light.
This touching scene is shattered by the arrival of the Lich King who reaches out and traps Alexandros soul inside a soul shard. Darion is furious. The Lich King then explains that he didn’t care if he had to sacrifice every Death Knight in his army, they were simply bait to lure out Tirion, his real quarry. This confession breaks the final bit of control he has over Darion and, as The Lich King channels a spell that will destroy Tirion and possibly everyone at Light's Hope, Darion says, “Not today” and throws the sword Ashbringer, through the air shouting “Tirion!”
Tirion reaches up his hand and, as it wraps around Ashbringer’s hilt, a torrent of Light streams down from the heavens, purifying the blade and freeing him from The Lich King’s spell. The Lich King falls back, shaken, and has to retreat. He cannot stand against the power of Ashbringer in the hands of a paladin of the Light, with the full might of Light’s Hope behind him. But he swears they will meet again, just not on consecrated ground.
Abandoned by their former master, the remaining Death Knights turn to Tirion Fordring. He speaks to them:
“We have all been witness to a terrible tragedy. The blood of good men has been shed upon this soil! Honorable knights, slain defending their lives -- our lives! And while such things can never be forgotten, we must remain vigilant in our cause.
The Lich King must answer for what he has done, and must not be allowed to cause further destruction in our world.
I make a promise to you now, brothers and sisters: the Lich King will be defeated! On this day, I call for a union.
The Argent Dawn and the Order of the Silver Hand will come together as one! We will succeed where so many before us have failed!
We will take the fight to Arthas, and we will tear down the walls of Icecrown!
The Argent Crusade comes for you, Arthas!”
Darion Mograine stands “So too do the Knights of the Ebon Blade. Although our kind has no place in your world, we will fight to bring an end to the Lich King. This I vow!’
This is the start of the alliance between the Knights of the Ebon Blade (those death knights that are free of Arthas’ control) and the Knights of the Argent Crusade (Tirion’s order), and while the death knights are still feared and hated over much of Azeroth it is a big step towards redemption and healing.
Darion fights in Northrend, he storms Icecrown Citadel and he helps to defeat the Lich King, and when the sword of Arthas is broken he gets back the soul shard that held his father and is finally able to free him. It is a happy reunion:
“Darion, my son. At last, I am able to lay my eyes upon you again.”
“Father. I feared for your... your sanity.”
“The Lich King tormented me without end, Darion. Endlessly, he sought to break my will, to force me to serve him, to bind me to his blade...Finally, when events demanded his full attention, he left me. The one memory, I clung to, Darion... The one thought that kept me from giving in...It was your sacrifice, my son, that again saved me from eternal peril.”
“Father... For you, I would give my life a thousand times.”