The blue female soldiers (Crane Corps) jumping from the wall to attack one or two monsters in A Grande Muralha seem to be a complete waste of well trained forces: they can kill one, maybe two or three monsters on each jump, and are apparently eaten quite often
Do they have a particular role explained in the movie, and the reason for this apparently ineffective tactical move?
If you have seen complete movie then you know that at the end,
Commander Lin Mae makes use of her Crane Corp abilities to swing from rope and get closer to Queen.
Apart from that Crane Corp is used to close combat Taotei. Death squad is used in similar way to attract Taotei and then cut them using blades within wall.
As there is no other mention of Crane Corp role other than defending close attack, in my opinion it's purely for demonstrating army's capability.