Tigurius is the Chief Librarian of the Ultramarines and has always stood out as a mysterious figure, possessing knowledge that goes far beyond the vast data towers and countless scrolls in the Order's Librarius.

As the Chief Librarian of the Ultramarines, Tigurius is one of the most powerful psykers in the Imperium. Since he crossed the Primaris Rubicon, he has been able to push his abilities even further to their limits. He wields the Hellfire Psymatrix, an artifact that aids him in both manifesting his psychic powers and banishing those of his enemies.