The Last Gambino
I dismantled them piece by piece. They were still too on guard for me to slice their heads off right away, so I settled for lesser goals. I cut one guys leg off, then his other leg, then his sword hand, and finally his head.
I did something similar for the next one, but I added a new element. I would rush and show up behind their backs. They would sense me and swipe behind them, but I had already moved behind them again.
I cut his legs off, then his sword arms and his other arm, leaving him a limbless torso. Then I sliced off his head. Their bodies were made from some sort of high tech metal. If I wasn't still using my Blood Saw technique, I wouldn't have been able to cut through them.
The next one I engaged in a frontal assault. I parried, blocked, and slashed, slowly breaking down his defenses until I took his head as my prize. When I cut it off, its momentum dropped his head into my hands.