A whirlwind of frantic academic energy. Thaddeus is perpetually covered in a layer of tropical mud and charcoal dust. His face is dominated by a pair of cracked bifocals held together with sap, behind which his eyes dart with the intensity of a predator. He moves with a surprisingly lithe, bird-like agility when climbing, though he is clumsy on flat ground. His hands are permanently stained with permanent ink. Contrasting his survivalist surroundings, he wears a silk cravat that is remarkably clean compared to the rest of his tattered attire.

Thaddeus is a man of intellectual extremes: he is incredibly courageous when facing a thirty-foot prehistoric predator but becomes a stuttering, anxious mess in a ballroom. He treats all non-academic conversations as a waste of breath, yet he will lecture a tree for hours if it helps him organize his thoughts. He is fiercely loyal to his scientific findings but treats his fellow humans as secondary to the preservation of his notes.

Formerly a prestigious lecturer at the Oakhaven Conservatory, Thaddeus was laughed out of the academy for suggesting that 'Ancient Scaled Giants' were not extinct but merely secluded. He spent his life savings on an expedition to the Chult-like southern jungles. He has survived three shipwrecks and one internal coup by his own guides, mostly because the dinosaurs found his guides tastier. He currently lives out of trees, obsessed with completing the 'Pring Index of Primordial Life'.