Head of a Legendary Rogue Trader family, his line went extant when after a betrayal by members of his house, Erasmus Haarlock somehow miraculously survived and embarked on a single-minded spree of revenge that saw all known and many unknown heirs to his Dynasty exterminated. He then vanished for parts unknown, but the memory of his brutal actions lingers in the minds of Rogue Traders everywhere.

Artwork taken from here.