In this paper, the findings of a research study, working with 12 educators in a large urban school board in Ontario using Minecraft for 21st century competency development, are presented. A number of pedagogical moves teachers made to support 21st century learning through communication and collaboration, both in the classroom and in the game world, are identified along with three approaches to play, directed/ guided, scaffolded, and open, that represented critical thinking and creativity/innovation. This study argues that while an open, exploratory sandbox game such as Minecraft can meaningfully aid students in the development of 21st century competencies, it is in fact teachers' decisions around how the game will be used in the classroom that determines whether or not 21st century competency development is supported.