Nobody likes an internet troll, but its been possible to take comfort in the idea most of them are just clowning around. Unfortunately, new research suggests thats not the case — trolls personalities correlate highly with sadism. A new study by Erin Buckels and her colleagues at the University of Manitoba found that trolls personalities are strongly linked to personality traits that form what some psychologists call the Dark Tetrad: sadism, narcissism, psychopathy, and Machiavellianism. Both trolls and sadists feel sadistic glee at the distress of others, the studys authors write.