This paper investigates attitudinal and behavioral factors for Consumer Engagement (CE) in Online Communities of Fortnite. We develop an approach based on an online experimental survey and the Response Time Testing (RTT) method, which allows measuring the level of accessibility of attitudes. The results reveal that the affective dimension of consumer attitude is the key indicator for consumer engagement in online communities of Fortnite, that the frequency of member’s participation in online communities of Fortnite defines the intensity level of consumer engagement toward the community, and that strongly engaged consumers are more likely to recommend the community. This study provides the first known implicit experimental investigation of consumer brand engagement in online brand communities.