I’m incredibly close to Master of Rath (rank 12, all challenges completed, I’ve just wanted to test new characters out a bit in between Rath sessions). I’m not sure who else I want to master since I’ve been picking up and dropping characters at random. I Used to play Montana, ISIC, Caldarius, and Reyna. Then I dropped the first 3, picked up Miko for a bit, and now I’m considering dropping him. I also just picked up Toby, he’s super fun, but then again so was Caldarius.
Edit: forgot to mention that I also play Benedict now, but once again, I have no idea how long that will last.