User blog comment:Toxictangent/Winter 2016 Progress Log/@comment-27330118-20160123020411

If your are well prepared for the next Event...

Let's says it will have 4 maps. Nagato & Mutsu would probably be a drop in E3 and E4. Mutsu is pretty "common" on the maps where she drop in Events (Looking at you, Fall 15 E-4 !).

I have Nagato & Mutsu, but I only use them as Boss Support Expedition during the Events.