‘They shall find no mercy from me. They are what they are. But we must not forget that most of them were noble warriors, and were led down this path by others. Words from a beloved leader can twist a man’s heart. It was, I believe, the Emperor’s fault. If He had not lied…’ Guilliman’s voice trailed away. He frowned. He questioned himself if that were really true. Maybe nothing could have stopped what had happened. Then he remembered the throne room, and the light, and that vast, inhuman soul touching his.

‘Did He really lie?’ asked Mathieu into the silence. He was barely breathing, caught up in revelation of his god’s words.

‘Yes. Yes He did. He knew the true nature of the warp, but kept it to himself. I deduce He wanted to keep my brothers and I from temptation, but instead ignorance left us vulnerable to it. Horus was a good man before he turned. He was proud and arrogant, that is for sure, but he believed in our father’s dream of the Imperium, and the love between them was so strong.’ Guilliman looked at Mathieu solemnly. He had once believed that, he truly had. Now he lied just like his father had. ‘Chaos found a way to use Horus’ love and pervert it. My father made a miscalculation, and it cost us all dearly.’

Mathieu let out the breath he was holding. ‘I marvel that you walked alongside the holy Emperor Himself, my lord. It is glorious to hear you speak of Him.’

‘I did,’ said Guilliman sadly. ‘I wish it could be so again.’ He had his own reasons for desiring that. He kept them to himself.

Mathieu searched for the right thing to say. ‘Gods are not beholden to the same laws as mortal men are, my lord. His reasons for lying are beyond our ken, even yours.’

Guilliman pulled a face at Mathieu.

‘Mathieu, you will not convince me that He is a god. He told me this Himself, many times. I spoke with Him like I speak with you now. The Emperor is remarkable, the pinnacle of humanity’s evolutionary path, and He has power that you and I cannot comprehend. But He was not and is not a god. He was a man. An exceptional man, but a man nonetheless. As a man, He made mistakes. As a man, He had his flaws.’

‘You are His son, my lord,’ said Mathieu. ‘You have said that you are not a man.’

‘I am not a normal man,’ said the primarch, ‘but I am still human, for all the many gifts the Emperor gave me, and so is the Emperor.’

Mathieu paced around the darkness of the exedra, his sandals plashing in the shallow puddles on the marble as he looked up at the lofty clock.