Although Four seems to be calm most of the time, they do get angry in "Lick Your Way to Freedom", "Why Would You Do This on a Swingset", "Fortunate Ben", and "Four Goes Too Far". Four was well-mannered in "X Finds Out His Value", however, and didn't screech. But in BFB, they have a mysterious, sadistic personality where they use their powers to harm the contestants just for their own fun.

In "Fortunate Ben", Four was shown to want a sense of dominance in the show and gets furious if talked back