Shapes rippled beneath Zadkiel’s robes as he shrugged his knife-edge shoulders. ‘Magister Lyræ is doing great work in your absence, Magister Saros. While you have been here on Prospero, Lyræ has been working hard back in Tizca. Your acolyte has uncovered the Library of Azariah. And he has wasted no time in deciphering its most famous text, The Canticles of Ahriman. From what I hear, he has already mastered the twelfth canticle and begun work on the thirteenth.’

He reached up and draped a writhing nest of fingers over Saros’ shoulder. ‘You can be proud. Very proud. Magister Lyræ has surpassed the meagre learnings you shared with him and tackled more elevated subjects. I imagine he will be keen to share what he’s found with you.’ He shrugged again. ‘Or perhaps, if he has gone so far into regions you could not comprehend, he will need to talk directly with the Red Monarch himself.’

Saros shook his head. He leant close and hissed through the mouth grille of his helmet. ‘Liar. No truth has ever passed your lips. How could Lyræ have discovered The Canticles of Ahriman? How could he understand what even Ahriman could not?’

As the sorcerer gripped Zadkiel’s robes tighter, the colours in the throne room boiled, flashing in response to Saros’ anger. The hymn faltered as Saros broke ranks, throwing the music into disarray.

‘Perhaps I should have consulted you before helping him?’ Zadkiel spoke quietly, as though genuinely contrite. ‘I hope I have not committed some kind of transgression by sharing what I knew? ­Magister Lyræ is only working on your behalf, after all. If he were able to reverse Ahriman’s rubric it would reflect well on you. ­Magister Lyræ only wishes to further your glory.’

Zadkiel knew this was not true. Saros’ acolyte would take any chance to usurp his master, and this threat was the perfect bait with which to hook Magister Saros. Every member of the court dreamed of somehow reversing the rubric that turned Magnus’ Legion into automatons. It would be the ultimate gift. But Zadkiel knew it was a fool’s errand. The rubric would never be reversed. The only way to win the Crimson King’s favour would be to forge him a new army, even greater than the old one.

The storm around Saros flashed white, brilliant with panic, causing the rest of the Rehati to stumble and break the circle, lowering staffs and glaives and turning to see the cause of the interruption.

‘You are a liar!’ cried Saros, grabbing Zadkiel by the throat and trying to shove him backwards.

There were no bones inside Zadkiel’s robes. He had surpassed the need for mortal flesh. The bird skull in his hood was carried by knots of serpents and even they were only ghosts, collapsing and dissolving as Saros tried to grip them.