This episode is pretty much Rose backstory. We do get some action though from back when Rose fought against the demons as a Battalion Commander, before the Rescue Squad was formed. Also, she has both of her eyes visible in the past, but otherwise she seems to be the same old Rose. She was freakishly strong before, just like she is now as well (she also already had her rabbit companion). Here is the group shot of her unit for posterity:

As for the action this episode, it seems like Rose had a propensity for throwing trees all the way back then as well. It was pretty much her go-to move for this fight sequence. It took a while for this demon guy to realize that his wind blades were not going to cut it when it came to fighting Rose. He eventually figured it out and pulled out the real sword.

It looks like the Rose backstory is going to be split over two episodes. I had though ahead of time that it would just be a single episode to sum it all up. The pace of this show has been pretty slow, which is usually a sign of a good adaptation, letting things develop and giving time to let plot points breathe and build up more naturally. However, I think this series could stand to have moved things along at a brisker pace. I think it is pretty clear that they have a particular ending point in mind for the first season and have backwards engineered how much and where to stretch things out to make it happen.