What is a Centaur in Fallout and is Thaddeus turning into one? *Warning - spoilers ahead for Fallout season 2. *View 2 Images Thaddeus assumed he was turning into a ghoul (Image: Amazon )‌What is a Centaur and what is Thaddeus turning into? Later, as the trio of Thaddeus, The Ghoul and Maximus advance towards the Las Vegas strip to confront Deathclaws, one of Thaddeus' arms detaches completely. During an earlier episode, whilst examining documents on a computer terminal, he stumbles across something labelled Forced Evolutionary Virus.