There was nothing much to say about it, to be honest. From the System perspective, it was merely an exchange of powers. No doubt it was a crazy duel that had no limits barred on them. Byakkou was shooting out electricity like nobody's business in all directions while Sei had used the element of earth to create walls so that the lightning strikes would not hit.
At first, System Rider Bakkou was able to intervene and do some damage and Sei played to the advantage of the Earth Element and created various rock barriers which did not allow Byakkou to strike through. It was only through brute force whenever he destroys the barrier that he shoots the lightning out but in return, those fists that penetrated through the barriers were met with counter attacks and Sei was extremely versatile in creating obstacles for Byakkou especially when they had fought hundreds of years ago.
Taking indefinite hiatus, rewrite chaps and post at times. tyvm