I watched it a couple of times and it looked pretty short and sweet. When it came to story boarding, it felt as if the shots where never going to end. So many shots in such a short clip, wow.
So there was a lot of back and forth shots from the defenders and the orcs, with the orcs gradually pounding their spears on the ground faster and faster.
I'd love to find the story board of this scene now.
Here is the clip
2:43 to 3:15
It is not my video, so I can not embed this clip.