The Phoenician’s legs were gone, replaced with a long serpent’s tail. His torso and face had become elongated, his chest altered to accommodate an additional pair of arms. Despite his obscene form, everything was weirdly perfect. The muscles in his bare chest were exquisitely defined. His skin was a gorgeous shade of lilac. The snakeskin of his lower half shone with jewelled colour, and he moved with grace to shame the aeldari. But all this was a perversion of his former beauty, if not of the very idea of beauty itself. It was too much, so perfect in its awful twisting of the human form that it went beyond the ability of the mind to process. Fulgrim’s new shape provoked revulsion by its very nature, while awing with the artfulness by which it had been done. By design, he was made to arouse and repulse equally.

His head in particular was changed, long and crowned with horns that rose crimson from his shock of white hair. His face, however, remained his own, a sickening joke to crown his dark transcendence. Seeing the features of his brother melded to this monster brought tears to Guilliman’s eyes.

Finely wrought ornaments jangled on Fulgrim’s limbs. Soft leather straps held long gloves in place on his right arms. The left arms were painted with delicate patterns, his fingers hung with chains and their nails stained clashing shades. Vile sigils decorated the buckles of his harness. More were tattooed upon his skin.

Fulgrim rose up on his banded tail, holding his four arms wide in the sickly light of the Heliopolis.

‘Behold, my brother. See! What the Emperor made, the Prince of Pleasure has improved upon. Am I not perfection? I was made to be a slave, but now I am free, and the companion to a greater god than our father can ever be.’

‘The Emperor is not a god,’ said Guilliman.

The ship quaked. A signifier in Guilliman’s helmet turned from red to green. The portside void generators had been disabled. Datascreed informed him the Fourth Company of the Iron Snakes was making a fighting withdrawal.

‘Do you still believe that?’ said Fulgrim. He inched forwards, swaying hypnotically. ‘He always did protest too much about that. You think I am a traitor, I know. You think I am selfish, and deluded, but no more so than dear, dear father. He gave me so much, not least a taste for treachery.’

Fulgrim leaned closer, close enough for his hot, perfumed breath to caress Guilliman’s armoured face. The cloying stink of it penetrated his breathing grille, making him gag. There was a scent of something rotten beneath the melange of spices, one note of decay in a bouquet of opulence.

There is the truth, thought Guilliman. The miasma of corruption, a murdered corpse hidden in a bed of flowers.