Nausicaans were one one biggest, fearsome, physically powerful naturally evolved humanoid species in the know galaxy until Enterprise fucked them up and turned them into pure pussies (see: Fortunate Son). But before that they were so badass that inflicting pain was a game to them. Hiring Nausicaan bodyguards was a universal sign of "fuck with me at your own risk". Nausicaans eat puppies and shit out nightmares.