How do members of extremist groups think about violence conducted by individual members on the group's behalf? We examine the link between extremism‐motivated violence and extremist groups through a case study of misogynist incels, a primarily online community of men who lament their lack of sexual success with women. To learn how misogynist incels talk about mass violence committed by members of their group, we conduct a qualitative content analysis of 3,658 comments relating to the 2018 Toronto van attack, in which self‐declared incel Alek Minassian drove a van into pedestrians, killing 10 and injuring 16. We find overwhelming support among self‐proclaimed incels for the attack and violence more generally. Incels viewed mass violence as instrumental, serving the following four main purposes: garnering increased attention, exacting revenge, reinforcing masculinity, and generating political change. Our findings indicate the need to examine misogynist incels as a potential terrorist group and male supremacism as a basis for terrorism.