This hellish scene was all because of my foolishness...
I indulged in psychic research, turning a deaf ear to The Emperor's warnings.
I allowed my sons to roam the Warp, letting them befriend the friendly "spirits" within.
I saw others as savages too afraid to leave their caves, while I saw myself as the sole sage, daring to point out that the flickering shadows at the cave entrance came from harmless flowers and trees.
Now, I knew I was wrong. Wrong beyond redemption, wrong past the point of return. The shadows guarding the entrance to humanity's cave—the Imperium of Man—were merely a tiny glimpse of that boundless terror.
And that tiny glimpse alone was enough to cast the Thousand Sons into the abyss.
Because of my foolishness, my sons suffered endlessly, with no release...
Magnus numbly executed his mutated sons. He did not use the psychic powers at which he excelled, but the purest strength of a Primarch, slaughtering their ever-swelling, twisted flesh.
Was this true death? Could they finally enjoy Serenity's peaceful rest?
Magnus knew perfectly well that it was impossible. Whenever he killed a Thousand Son who had suffered from mutation and lost his mind, undisguised demonic laughter rang out above him, mocking him for killing his own sons. All he had done was drive their shattered souls from one hell into another.
The minced flesh before him could no longer be identified. Magnus kept hacking at it with an Adeptus Custodes weapon like a machine, only coming back to himself when a despairing sob reached his ears.
"Father... Brother Samesh is dead. He couldn't be any deader..."
Magnus stopped and turned to look at the few remaining sons who still retained human forms and sanity. They had helped with the slaughter just now.
"Ahriman. Khayon."
Magnus spoke,