As a child, he was tortured by the Daemon Prince Kholoth who took one of his eyes and ears before destroying the rest of his village. Tyrus was saved by Inquisitor Covonis who then took Tyrus under his wing as an apprentice. Covonis was killed on Epsilon Regalis by Kholoth but Tyrus successfully banished Kholoth again, taking his master's power armour and force sword. He was then elevated to the full rank of Witch Hunter and Inquisitor.
Tyrus is highly active as an internal policer of heresy. He is known for extreme and bloody purges on regular occasions. He is also known to chase heretical inquisitors as strongly as he does witches. He has a strong hatred of all kinds of psykers, even his fellow inquisitors. His policy on guilt is based on religious testing and arcane methodology. The Trial by Balance, Ordeal of the Blade and Trial by Holy Seal are often used by him, while his favorite method is forcing the accused to consume a jug of holy water - if they choke, then they are considered heretic and killed. He is also known to use the Emperor's Tarot to determine innocence or guilt.