TYSM!! M.K is the route Ailin's been writting for the longest (4-5 years now, 3 if you only conside the most recent version of the story) and is the most challenging because of how toxic is it compared to the rest. We had to tone it down many times before coming to an agreement on it.
However Midnight's and Phantom's are also hard as we have to make the heists and two possible explanations of how it can work (how MC percieves it and how it was actually done)