Tyrus was being trained in the role of Chaplain under the tutelage of Chaplain Grabthar, when both were assigned to the ill-fated Silica campaign force. The mobilisation of the Chapter after Ghazghkull Thraka invaded Armageddon once more led to the enforced abandonment of the forces on Silica IV.

Tyrus flourished on Silica Iv despite being cut off from the chapter and fleet of the Salamanders, displaying a level of self-reliance worthy of Vulkan himself.

It was when the Night Lords warband by the infamous "Lord" Rork made their presence on Silica IV known with a series of sickeningly brutal raids against the major population centres, that Tyrus was truly forged as warrior.

Tyrus' mentor led the 30 marines now known as "The Abandoned" in a direct confrontation with the Traitors, as dictated by the Codex Astartes. Grabthar was killed alongside all but a handful of his troops as the well-prepared Night Lords led a merciless counter-attack. Tyrus was one of the lucky few, though he was wounded, he managed to escape the battle and heal.

Revisiting the scene of the battle the following dawn, Tyrus took up Grabthar's Rosarius and acted as chaplain to the few men who remained. Such was the inspiration provided by Tyrus' unshakeable faith and his tales of Vulkan's heroics, that the survivors rallied around him.

Tyrus and his tiny force conducted a year-long guerilla campaign against the heretical marines, and they succeeded in wiping out every Night Lord on the planet without further loss, freeing Silica from the yoke of the blasphemous powers.

When Tyrus returned to Nocturne, after the battlebarge Holy Conflagration picked up his signal, he was invited by Tu'shan himself to join the elite Firedrakes. Tyrus refused, and instead requested to be permanently assigned as Chaplain of the Second Company. Tu'Shan agreed, and Tyrus was presented with a Firedrake hammer, crafted in the heat of Mount Deathfire, as both a badge of office and as a reminder of the choice that Tyrus had made.