The thing is that he can basically teleport as easily as blinking, and with great precision. Fighting him is like fighting air. Offensively he has the Rasengan, which would do massive damage to Beowulf before he can even tell what's happening.
In the video I linked he gets cut in two and the halves just rejoin. His body is essentially a large colony of snakes transformed into a human - from what I can tell he only needs one to survive.