"The Agile Musical Mind: mapping the musician's act of creation" explores a tentative approach towards developing a discourse on the musician's creative act, starting from the artist's viewpoint. By considering creativity as a language game, present in different performative domains of human acts, this chapter looks for family resemblances. It will start by an inquiry into the complexity of the musician's act. The various aspects of the composer's as well as the performer's creativity will point to the integration of the artist's web of practice in creative acts, ranging from preparation to performance. Drawing on theories on creativity originating in linguistics and music, two cognitive integration mechanisms -- or family resemblances -- inherent to 'creativity' in music and other domains are explored: unexpected expectation or suspended fulfilment of expectation and creative duality of content and form based on multimodal and idiosyncratic blending of cognitive spaces. Suspended fulfilment of expectationis inherent to the dynamics of human life: we all expect some things to happen but what actually happens can exceed our expectations. We will consider how musical creation is constructed following complex culturally developed patterns of (unexpected) expectation, appreciated by both musicians and audience. Holistic multidimensional integration is the powerful capacity of humans to combine different strands, thoughts, experiences and perceptions into a new creation, as well as to understand or perceive certain manifestations as meaningful by combining knowledge and experience of different perceptual and cognitive domains.