'Too late, too late,' said Horus. He looked up at his brother. For a moment their eyes met, and Russ saw nothing but regret in his brother's face. Then Horus smiled, and the regret was replaced by triumph.

Horus took a deep, rumbling breath, the sort taken by men on the cusp of death.

'It is too late, Leman of the Russ,' said Horus. 'Far too late for you.'

'Horus!' shouted Russ. 'Hear me!'

Horus replied so loudly warriors on both sides stumbled and clutched at their ears.

'I hear you, and I defy you.' Horus' words echoed down the aeons, coming from a place beyond time and space. 'This universe will burn as countless others have burned before it! There can be no victory against Chaos. If you cannot accept its power and its glory, then you shall die. The Emperor is doomed. I will kill Him myself.'

Before Russ could react, Horus punched forwards with his talon, slamming it hard into the injured side of Leman Russ. The boom of the claws' energy fields rolled out over the battlefield, drowning out the noise of battle. Russ roared with pain as the talon raked fresh cuts through his armour and gouged deeply into his flesh. The barbs ripped away chunks of muscle, the energy fields scorched his bones. With a contemptuous flick, Horus threw him off the ends of his claws, hurling Russ across the chamber.

Russ skidded to a halt at the foot of a profane painting, the Emperor's Spear clattering down beside him. Smoke issued from the rents I carved into the armour of Elavar by Horus' talon.

Horus grabbed the handle of his maul, forcing his heavily armoured body back upright. He gathered his dark majesty to himself again like a cloak. The haggard, suffering figure was gone. Russ could not be sure he had really seen it.

'So you were good enough, after all, brother. You could have killed me. You should not have hesitated. This weakness is what will cost our father victory. You so nearly won.'

Horus strode forwards, his maul raised to deliver the killing blow. 'When your soul is cast from you, and you are adrift in the warp, then you will know the truth as I do, brother. Before your essence is devoured by the gods our father denies, you will know you were wrong to deny me.'

Russ looked up weakly. Blood ran between his teeth. At least one of his lungs was punctured, and his secondary heart had been injured. His flesh burned with the efforts of his primarch's physiology to heal him, but his hurts were graver than the marks on his armour suggested. His chest was a mess of snapped ribs and pulped organs. The wounds were terrifyingly similar to those he had suffered in the Underverse, and he saw them now as prophecy.