The purpose of this study was to explore how aspiring school leaders grappled with threshold concepts related to educational leadership within mixed reality simulations. An exploratory collective case study was used to understand the experiences of the participants (n = 12) who practiced mixed reality simulations of conferences with subsequent coaching in a simulation laboratory in one year of their educational leadership preparation program. There were three data sources: video observational data of the performances within the simulations and after simulation coaching, both peer and mentor; individual semi-structured interviews; and reflective documents following the simulations. Using both deductive and inductive approaches to data analysis, we found that purposefully planning for using threshold concepts within the simulations led to separation, liminal and professional portals of learning. Participants sometimes oscillated backward into a previous portal when they demonstrated growth in some, but not all, leadership behaviors within the simulated conferences. Liminality, by its very nature, is anti-structured, changeable, and ambiguous and these changes were evident in our findings. Discussion and implications for educational leadership programs are offered.