I remember an interview with Mazin a number of years ago. It might have been with Brian Koppelman.

Mazin said that he made a very conscious and calculated decision to move his career into other genres. He asked his agent and reps to start putting his name into contention for things that he normally would not be considered for.

I think he said the first project he secured on this new trajectory was writing on The Huntsman: Winter's War (the sequel to Snow White and the Huntsman).