Entrepreneurs can benefit from the communities they build. Therefore, many entrepreneurs create online communities that allow self-selected stakeholders, such as customers, crowd investors, or enthusiasts, to interact with the venture and other like-minded individuals. However, research on how entrepreneurs can successfully engage community members and grow such online communities is only slowly emerging. In particular, it is unclear if, how much, and which content entrepreneurs should contribute to foster engagement in different types of communities and which role these community types play in the community’s overall growth. Based on a longitudinal case study in the video game industry, we first theorize and show that—depending on the community type—both too much and too little entrepreneur-provided content fails to leverage community engagement potential and that different communities require more or less diverging content. We then theorize and show that community growth is largely driven by engagement in open communities, such as those hosted on social media. We outline the implications this has for entrepreneurs, our understanding of online communities, and entrepreneurial communities more generally.