It gets forgotten a lot, but I should remind casual viewers that there were fight scenes in Volume 5 finale, both with the Wight Fang outside and the HELM inside. A part of this I think it's because there wasn't a real explosive finish to the fight, as when we cut back, we see the remaining three (Leo having fled earlier) being cornered. No decisive finishing move, it's just...done. Oz did said they'd have to wear Hazel down, which I imagine may have gotten monotonous to animate and watch.
Another part of it is because the real showdown is between Yang and Raven. But rather than a climatic duel, it's a battle of wills, with Raven trying to justify herself and Yang not having it. It's a testament to Yang's character development that instead of throwing down, she convinces Raven to give up the Relic, seeing the disconnect between Raven's immediate plan and her intent. The battle Yang wins by using her head, not her fists.
