And so, the first part of our tale comes to an end. Thoth’s quill may rest for a time, as my hosts pore over these words and seek weaknesses between the dictated lines. But I doubt it will rest for long. They will want more. They have been told of the Black Legion’s genesis, now they will ask of its birth and first battles, as well as the Thirteen Crusades that followed. There is still so much to tell. So many wars won and lost; so many brothers and enemies fallen into memory.

After the Canticle City came the Illumination, when we battled those who would not swear allegiance to the Warmaster and sought to end our rise. During that era we traversed the Empire, of the Eye, ending the Legion Wars with our ascendance above the Nine, and one by one the primarchs bowed before Abaddon. Some willingly, some only grudgingly, and one who had to be brought to his knees. But all of them bowed in the end: Lorgar, Perturabo, Fulgrim, Angron, an my father Magnus…even Mortarion, who came closest of all to slaying us through his holy plagues.

And after that came our First Crusade. Imperial record remembers it as the first time the Nine Legions broke free of the Eye and returned to the galaxy in strength against an unprepared Imperium. The Nine Legions remember it for the triumph at Uralan, where the Warmaster claimed his daemon blade, Drach'nyen. We of the Ezekarion have a different recollection - or, at least, one with a profoundly different focus. Perhaps the new regents of the Imperium did not expect our return and so were unprepared to face us, but not all of the Emperor’s servants had forgotten its wayward sons.

I can see him still: that ancient Templar-king sitting upon a throne of hand-carved bronze, his armoured fingers laced around the hilt of his great blade. I remember how, to my secret sight, his immense pride and absolute faith in our grandsire turned his aura into a raging halo of pearl and gold.
‘So you have returned’.His voice was deep, as old as time itself, yet uncracked by the years it carried. 'I never doubted you would’. He rose smoothly from his throne, his back straight, the Sword of the High Marshals held loosely in one fist. By that point he was a veteran of more than a thousand years. Age had ravaged him, yet he burned with life.

Abaddon stepped forward then, gesturing silently for us to lower our weapons. He inclined his head in respectful greeting.
'I see time has blackened your armour as it has our’.
The ancient Templar descended the three steps from his throne his gaze fixed on the Warmaster’s face.
'I looked for you. As Terra burned in the fires of your father’s heresy, I hunted for you, day and night. Always lesser men blocked my way. Always they died so that you might live’. 
He came to a halt no more than two meters from Abaddon.
'I never stopped searching for you, Ezekyle. Not through all these long years’.Abaddon bowed then, with no hint of mockery. Not in his eyes, nor in his heart. Ezekyle had always cherished valiant foes, and none were more valiant than this knight.
'I am honoured, Sigismund’.
Both of them raised their blades…

—  Iskandar Khayon of the Black Legion
(The Talon of Horus by Aaron Dembski-Bowden)