While Merilli's Force Wraiths were huge, standing nearly four meters tall and resembling nightmare versions of Wookiees that were fearsome and devastating in combat, Jedgar's Wraiths were smaller, insectoid things which were roughly two meters tall. In contrast to Merilli, Jedgar used his as spies or guards and, occasionally, warriors when he needed combat fodder. Additionally, while Merilli commanded her Wraiths, Jedgar often remained in contact with his, and used them as his eyes and ears in far-off locations.
Any beings who had faced Force Wraiths and lived to tell the tale remembered the incident much as a child remembers a bad dream. If there were ever any true monsters in the galaxy, Force Wraiths were them.