When Mortarion, Primarch of the Death Guard, allied his legion with the forces of Warmaster Horus against the Emperor of Mankind, he did not know the price that would be paid for his treachery. One amongst the Death Guard knew full well though; his name was Typhon and he had been recruited like so many others into Mortarion's forces on the feral world of Barbarus where the Primarch had grown up. Barbarus was home not only to men but to inhuman overlords that preyed upon them.

In his early days Mortarion had overthrown these monstrosities, however there were many crossbreeds resulting from their cruel dominion. The bloodlines were not easy to follow and Mortarion had more pressing concerns. Typhon was of such a bloodline. He possessed formidable psychic powers that allowed him to navigate the mist-shrouded world of Barbarus freely. These were merely latent powers at this time and would only develop with time and training.

When the Death Guard began to recruit on Barbarus it was Typhon's warrior skills that marked him out. In modern times the process is far more exacting -and should be - as much more is known about preserving the purity of the gene-seed, and a Space Marines chapter of a thousand men can be selective about its recruits. In the days of the Great Crusade the legions needed recruits with a good right arm and the courage to follow their Primarchs into battle. When it was realised that Typhon was also a Psyker he was welcomed even more as each legion was building up its strength in Librarians.

So it was that the Death Guard already harboured a tainted soul. Even as Mortarion led his legion on the Emperor's Great Crusade, Typhon communed with the Dark Powers. They already favoured him, and with their aid Typhon rose to the rank of Captain-Epistolary, commander of the battleship Terminus Est and a full company of the Death Guard. When the Death Guard joined Horus, it was Typhon who slew the Death Guard's Navigators claiming their loyalty was still to the Emperor. It was Typhon who promised Mortarion that his powers could lead the Death Guard through the Warp to Terra and it was Typhon who led them to damnation, becalmed in the Warp, adrift and helpless.

The journey to Terra was the first time that the price of turning on the Emperor was truly paid by one of the Traitor Legions. It was a nightmare that would mark them in the most horrific way. Time flows differently in the Warp and the ordeal that Typhon led them into could have lasted days or centuries. By the end none of the warriors aboard the Death Guard battle barge Terminus Est could reckon how long they had been becalmed along with the rest of their fleet. By the time the full horror emerged there were none of them able to resist it even if they had wanted to.

One by one the Death Guard were afflicted with a plague so virulent that their Multi-lung and Oolitic Kidney failed to protect them. They remained conscious but were paralysed and helpless to do more than endure the burning pain that filled their bodies. Only their unquenchable instinct for survival preserved them.

That instinct was pushed to its very limit before the background hum of the warp shield generators died to be replaced by a distant vibration that grew steadily more intense. Suddenly it turned into the buzz of a million wings as countless black, bulbous, Warp-spawned flies poured through every bulkhead. This was the Destroyer, foulest of Nurgle's plagues. They swarmed over the paralysed Death Guard, feeding off their sweat, infecting their wounds and infesting every orifice. Throughout the vessel each body twitched uncontrollably as the plague flies laid their eggs within them. Flesh and armour swelled as the corruption filled them, bloating and distending until it burst leaving entrails and pus-filled lesions hanging from their wracked bodies.

On the bridge the ship's master, Typhon, was the first to stir, through a miasma of death he rose to his feet. From deep within him came a rattling, phlegm-laced roar.

"More."

All over the vessel the plague flies left their hosts and flew or crawled to him. The tide flowed into him ceaselessly until it was all gone. Impossibly the giant figure still stood, no longer Typhon, now he was host to the Destroyer Hive, the favoured son of Nurgle. Now he was Typhus.

Truly he had received his reward from his true master, Nurgle, Lord of Decay, and the god he had served even before the corruption of Mortarion. Whilst he remained subordinate to Mortarion, it was clear that Typhus considered that he need only call Nurgle 'Master'.

In the Eye of Terror Mortarion shaped his daemon world to resemble Barbarus. Typhus was sickened by the sentimentality. His loyalty was to Nurgle and Nurgle waxed strong when mortals feared death. Taking his ship and his followers Typhus returned again and again to the mortal realm and the legend of the traveller, the Herald of Nurgle was born. The rewards granted him by Nurgle are testament to a score of blighted worlds and countless damned souls.