Background
Trassk wasn't always so fanatical to the Scorekeeper. He started a small group called the Krayt Breaths with a human called Greves Koller, hiring themselves out on missions that required brute strength and force. Trassk and Greves became close friends, bonded by close saves and after battle celebrations. Then, they were approached by a member of (some criminal outfit, can't think of a good one). Trassk didn't want to do the dirty work of a criminal outfit, but Greves was persuaded by the sum of money offered. Greves slipped something in Trassk's drink and then had him tossed in one of their cells. Distraught by both the betrayal of a close friend and the loss of his Jagganth points in the eyes of the Scorekeeper, Trassk broke out of the cell and vowed to the Scorekeeper to dedicate his life to her.
Motivation
Trassk lives his life in devotion to the Scorekeeper. He respects the elders who have grown from their many experiences, he eschews the corruption of blasters in favor of honorable melee weapons and those bestowed upon him by the Scorekeeper, he seeks to grow his Jagganth points, is loyal to friends and deals, and deals harshly with those who cross him.