Originally Posted by Drip

It's repeatable throughout the day. I forgot the exact rewards though, I think about 530 sake, but I didn't 3* it because I had some squads who were a bit too fast (note to self: try the unit with even speeds next time).

Anyway, here's the map and what I remember from it:

Yeah, it rewards 530 sake and summons the same SG as E4.

Warp node to the right of your Squad 4 leads to that empty node sandwiched by the locked nodes and the boss node on the bottom-left side. Because of lack of stamina, I have yet to try other configurations to see where the 2 middle warp nodes are leading to.

On one of the special map runs, I only lost my main 784 squad to the last boss because the girls weren't activating skills. *facepalm* Otherwise, I didn't really have much trouble getting the 3* on this one, just takes some speed tweaking.